This ClipArt gallery includes 147 illustrations of spiders, mites, scorpions, and other members of the arachnid class.

"An order of the class Arachinida, includes those insects, as the mites, ticks, itch-insects, etc., which are without a definite line of demarktationbetween the unsegmented abdomen appearing united in one."-Whitney, 1902

Acarida

"An order of the class Arachinida, includes those insects, as the mites, ticks, itch-insects, etc.,…

"Four stages in the development of the trilobite Agnostus nudus. A, Youngest stage with no mesosomatic somites; B and C, stages with two mesosomatic somites between the prosomatic and telsonic carapaces; D, adult condition, still with only two free mesosomatic somites." — The Encyclopedia Britannica, 1910

Agnostus Nudus

"Four stages in the development of the trilobite Agnostus nudus. A, Youngest stage with no mesosomatic…

The name of animals of the class Arachnida. Scorpions have an elongated body, suddenly terminated by a long slender tail formed of six joints, the last of which terminates in an arcuated and very acute sting, which effuses a venomous liquid.

Arachnid Scorpion

The name of animals of the class Arachnida. Scorpions have an elongated body, suddenly terminated by…

"Mygale cæmentaria, typical of Araneida. A, female, natural size: At, cheliceræ; IV', pedipalpi; V', VI' maxillary feet; VII', VIII', thoracic feet; Cth, cephalothorax. B, last joint of pedipalpus of male, much magnified."-Whitney, 1902

Araneida

"Mygale cæmentaria, typical of Araneida. A, female, natural size: At, cheliceræ; IV', pedipalpi;…

"Diagram of the arterial system of A, Scorpio, and B, Limulus. The Roman numerals indicate the body somites and the two figures are adjusted for comparison. ce, Cerebral arteries; sp, supra-spinal or medullary artery; c, caudal artery; l, lateral anastomotic artery of Limulus. The figure B also shows the peculiar neural investiture formed by the cerebral arteries in Limulus and the derivation from this of the arteries to the limbs, III, IV, VI, whereas in Scorpio the latter have a seperate origin from the anterior aorta." — The Encyclopedia Britannica, 1910

Arterial System

"Diagram of the arterial system of A, Scorpio, and B, Limulus. The Roman numerals indicate the body…

"Atypus sulzeri. (Vertical line shows natural size.)"-Whitney, 1902.

Atypus

"Atypus sulzeri. (Vertical line shows natural size.)"-Whitney, 1902.

"The Cheese-mite, <em>Acarus domesticus</em>, and others are parasitic upon or beneath the skin of man and other animals." &mdash; Goodrich, 1859

Cheese-mite

"The Cheese-mite, Acarus domesticus, and others are parasitic upon or beneath the skin of man…

A spider's web or net.

Cobweb

A spider's web or net.

A spider's web.

Cobweb

A spider's web.

Horseshoe crabs represent an order called Xiphosura, from the fact that the end of the abdomen is furnished with a long sword-like spine.

Horseshoe Crab

Horseshoe crabs represent an order called Xiphosura, from the fact that the end of the abdomen is furnished…

An illustration of an adult horseshoe crab from the dorsal aspect. The horseshoe crab or Atlantic horseshoe crab (Limulus polyphemus) is a marine chelicerate arthropod. Despite its name, it is more closely related to spiders, ticks, and scorpions than to crabs. Horseshoe crabs are most commonly found in the Gulf of Mexico and along the northern Atlantic coast of North America. A main area of annual migration is the Delaware Bay, although stray individuals are occasionally found in Europe.

Horseshoe Crab (Adult)

An illustration of an adult horseshoe crab from the dorsal aspect. The horseshoe crab or Atlantic horseshoe…

An illustration of a young horseshoe crab from the dorsal aspect. The horseshoe crab or Atlantic horseshoe crab (Limulus polyphemus) is a marine chelicerate arthropod. Despite its name, it is more closely related to spiders, ticks, and scorpions than to crabs. Horseshoe crabs are most commonly found in the Gulf of Mexico and along the northern Atlantic coast of North America. A main area of annual migration is the Delaware Bay, although stray individuals are occasionally found in Europe.

Horseshoe Crab (Young)

An illustration of a young horseshoe crab from the dorsal aspect. The horseshoe crab or Atlantic horseshoe…

The crab louse can live in almost any form of human hair, leading to its other common name of pubic louse.

Crab-louse

The crab louse can live in almost any form of human hair, leading to its other common name of pubic…

Scorpions are any arachnid of the order Scorpionida. Unlike the majority of arachnid species, scorpions are viviparous. The young are born one by one, and the brood is carried about on its mother's back until the young have undergone at least one moult. All known Scorpion species possess poison or venom. Scorpions use their venom to kill or paralyze their prey so that it can be eaten; in general it is fast-acting, allowing for effective prey capture.

Scorpion

Scorpions are any arachnid of the order Scorpionida. Unlike the majority of arachnid species, scorpions…

"Cryptostemma Karschii, one of the Podogona. Dorsal view of male. III to VI, The third, fourth, fifth and sixth appendages of the prosoma. a, Movable (hinged) sclerite (so-called hood) overhanging the first pair of appendages. b, Fused terga of the prosoma followed by the opisthosoma of four visible somites. an, Orifice within which the caudal segments are withdrawn. E, Extremity of the fifth appendage of the male modified to subserve copulation." &mdash; The Encyclopedia Britannica, 1910

Cryptostemma Karschii

"Cryptostemma Karschii, one of the Podogona. Dorsal view of male. III to VI, The third, fourth, fifth…

"Cryptostemma Karschii, anterior aspect of the prosoma with the "hood" removed. I to IV, first to fourth appendages of the prosoma; a, basal segment of the second pair of appendages meeting its fellow in the middle line." &mdash; The Encyclopedia Britannica, 1910

Cryptostemma Karschii

"Cryptostemma Karschii, anterior aspect of the prosoma with the "hood" removed. I to IV, first to fourth…

"Cryptostemma Karschii, one of the Podogona. Vental view. I to VI, The six pairs of appendages of the prosoma, the last three cut short. 1, 2, 3, 4, The four somites of the opisthosoma. a, Visible hood overhanding the first pair of appendages. b, Position of the genital orifice. c, Part of 3rd appendage. d, Fourth segment of 2nd appendage Observe that the basal segment of appendage III does not meet its fellow in the middle line." &mdash; The Encyclopedia Britannica, 1910

Cryptostemma Karschii

"Cryptostemma Karschii, one of the Podogona. Vental view. I to VI, The six pairs of appendages of the…

"Cryptostemma Karschii. Extremity of the fifth pair of appendages of the female for comparison with that of the male." &mdash; The Encyclopedia Britannica, 1910

Cryptostemma Karschii

"Cryptostemma Karschii. Extremity of the fifth pair of appendages of the female for comparison with…

"Dalmanites limulurus, Green. One of the Phacopidae, from the Silurian, New York." &mdash; The Encyclopedia Britannica, 1910

Dalmanites

"Dalmanites limulurus, Green. One of the Phacopidae, from the Silurian, New York." — The Encyclopedia…

"Deiphon Forbesii, Barr. One of the Cheiruridae. Silurian Bohemia." &mdash; The Encyclopedia Britannica, 1910

Deiphon

"Deiphon Forbesii, Barr. One of the Cheiruridae. Silurian Bohemia." — The Encyclopedia Britannica,…

"A parasite sometimes present in the human hair follicles." &mdash;Davison, 1906

Demodex Folliculorum

"A parasite sometimes present in the human hair follicles." —Davison, 1906

"Portion of a similar embryo at a later stage of growth. The praegenital somite, VII PrG, is still present, but has lost its rudimentary appendages; go, the genital operculum, left half; KM, the left pecten; abp4 to abp7, the rudimentary appendages of the lung-sacs." &mdash; The Encyclopedia Britannica, 1910

Embryo

"Portion of a similar embryo at a later stage of growth. The praegenital somite, VII PrG, is still present,…

"Entosternum of scorpion (Palamnaeus indus, de Geer); dorsal surface. asp, Paired anterior process of the subneural arch. snp, Sub-neural arch. ap, Anterior lateral process. lmp, Lateral median process. pp, Posterior process. pf, Posterior flap or diaphragm of Newport. m1 and m2, Perforations of the diaphragm for the passage of muscles. DR, the paired dorsal ridges. GC, Gastric canal or foramen. AC, Arterial canal or foramen." &mdash; The Encyclopedia Britannica, 1910

Entosternum

"Entosternum of scorpion (Palamnaeus indus, de Geer); dorsal surface. asp, Paired anterior process of…

"Entosternum of one of the mygalomorphous spiders; ventral surface. Ph.N., pharyngeal notch. The posterior median process with its repetition of triangular segments closely resembles the same process in Limulus." &mdash; The Encyclopedia Britannica, 1910

Entosternum

"Entosternum of one of the mygalomorphous spiders; ventral surface. Ph.N., pharyngeal notch. The posterior…

"Dorsal surface of an entosternum. Ph.N., pharyngeal notch." &mdash; The Encyclopedia Britannica, 1910

Entosternum

"Dorsal surface of an entosternum. Ph.N., pharyngeal notch." — The Encyclopedia Britannica, 1910

"A genus of spiders, the type of a family called Epeirdae. They are of those spiders which have only a pair of pulmonary sacs and spiracles; construct webs with regular meshes, formed by concentric circles and straight radii; and are furnished with a pair of almost contiguous eyes on each side; other four eyes forming a quadrangle in the center." &mdash; Chambers, 1881

Epeira Diadema

"A genus of spiders, the type of a family called Epeirdae. They are of those spiders which have only…

"Eurypterus Fischeri, Eichwald. Silurian of Rootzikil. Restoration after Schmidt. The dorsal aspect is presented showing the prosomatic shield with paired compound eyes and the prosomatic appendages II. to IV. The small first pair of appendages is concealed from view by the carapace. 1 to 12 are the somites of the opisthosoma; 13, the post-anal spine." &mdash; The Encyclopedia Britannica, 1910

Eurypterus Fischeri

"Eurypterus Fischeri, Eichwald. Silurian of Rootzikil. Restoration after Schmidt. The dorsal aspect…

"Section through the lateral eye of Euscorpius italicus. lens, Cuticular lens. nerv.c, Retinal cells (nerve-end cells). rhabd, Rhabdomes. nerv.f, Nerve fibes of the optic nerve. int, Intermediate cells (lying between the bases of the retinal cells)." &mdash; The Encyclopedia Britannica, 1910

Euscorpius Italicus

"Section through the lateral eye of Euscorpius italicus. lens, Cuticular lens. nerv.c, Retinal cells…

Close view of a spiders foot.

Spider Foot

Close view of a spiders foot.

"Galeodes sp., one of the Solifugae. Ventral view to show legs and somites. I to VI, The six leg-bearing somites of the prosoma. opisth I, First or genital somite of the opisthosoma. ge, Site of the genital aperture. st, Thoracic tracheal aperture. l2, Anterior tracheal aperture of the opisthosoma in somite 2 of the opisthosoma. l3, Tracheal aperture in somite 3 of the opisthosoma. a, Anus." &mdash; The Encyclopedia Britannica, 1910

Galeodes

"Galeodes sp., one of the Solifugae. Ventral view to show legs and somites. I to VI, The six leg-bearing…

"Galeodes sp., one of the Solifugae. Ventral view with the appendages cut off at the base. I to VI, Prosomatic appendages. s, Prosomatic stigma or aperture of the tracheal system. 1, First opisthosomatic sternite covering the genital aperture g. 2, Second opisthosomatic sternite covering the second pair of tracheal apertures sp1. Sp2, The third pair of tracheal apertures. 10, The tenth opisthosomatic somite. an, The anal aperture." &mdash; The Encyclopedia Britannica, 1910

Galeodes

"Galeodes sp., one of the Solifugae. Ventral view with the appendages cut off at the base. I to VI,…

"Galeodes sp., one of the solifugae. Dorsal view. I to VI, Bases of the prosomatic appendages. o, Eyes. a, Lateral region of the cephalic plate to which the first pair of appendages are articulated. b, Cephalic plate with median eye. c, Dorsal element of somites bearing third and fourth pairs of appendages. d, Second plate of the prosoma with fifth pair of appendages. e, Third or hindermost plate of the prosoma beneath which the sixth pair of legs is articulated. 1, 2, 9, 10, First, second, ninth and tenth somites of the opisthosoma. an, Anus." &mdash; The Encyclopedia Britannica, 1910

Galeodes

"Galeodes sp., one of the solifugae. Dorsal view. I to VI, Bases of the prosomatic appendages. o, Eyes.…

"Galeodes sp., one of the Solifugae. I to VI, The six prosomatic limbs cut short. o, The eyes. b, c, Demarcated areae of the cephalic or first prosomatic plate corresponding respectively to appendages I, II, III, and to appendage IV. d, Second plate of the prosoma-carrying appendage V. e, Third plate of the prosoma-carrying appendage VI. The prae-genital somite is absent. 1, First somite of the opisthosoma. 2, Second do. S, Prosomatic tracheal aperture between legs IV and V. S' and S'', Opisthosomatic tracheal apertures. 10, Tenth opisthosomatic somite. an, Anus." &mdash; The Encyclopedia Britannica, 1910

Galeodes

"Galeodes sp., one of the Solifugae. I to VI, The six prosomatic limbs cut short. o, The eyes. b, c,…

"Closeup of a garden spider's foot, showing the 'combs' for clinging to webs."&mdash;Finley, 1917

Foot of a garden spider

"Closeup of a garden spider's foot, showing the 'combs' for clinging to webs."—Finley, 1917

"Some spiders, like the <em>Ctenizae</em>, close the mouth of their subterranean resdence with a most ingeniously-constructed trap-door, which the inhabitant closes with the utmost pertinacity when any attempt is made to invade the privacy of his domicile. Hence these, of which several species are found in the south of Europe and on the shores of the Mediterranean, are generally known as <em>Trap-door spiders</em>." &mdash; Goodrich, 1859

Garden-spider and trap-door spider

"Some spiders, like the Ctenizae, close the mouth of their subterranean resdence with a most…

"Some, of which the Common Garden Spider, <em>Epeira diadema</em> is an excellent example, construct a beautiful net, composed of stout radiating lines, intersected at tolerably regular intervals by circular filaments." &mdash; Goodrich, 1859

Garden-spiders

"Some, of which the Common Garden Spider, Epeira diadema is an excellent example, construct…

"Garypus litoralis, one of the Pseudoscorpiones. Ventral view. I to VI, Prosomatic appendages. o, Sterno-coxal process of the basal segment of the second appendage. 1, Sternite of the genital or first opisthosomatic somite; the prae-genital somite, though represented by a tergum, has no seperate sternal plate. 2 and 3, Sternites of the second and third somites of the opishosoma, each showing a tracheal stigma. 10 and 11, Sternites of the tenth and eleventh somites of the opisthosoma. an, Anus. " &mdash; The Encyclopedia Britannica, 1910

Garypus Litoralis

"Garypus litoralis, one of the Pseudoscorpiones. Ventral view. I to VI, Prosomatic appendages. o, Sterno-coxal…

"Garypus litoralis, one of the Pseudoscorpiones. Dorsal view. I to VI, The prosomatic appendages. o, Eyes. Prae-gen, Prae-genital somite. 1, Tergite of the genital or first opisthosomatic somite. 10, Tergite of the tenth somite of the opisthosoma. 11, The evanescent eleventh somite of the opisthosoma. an, Anus." &mdash; The Encyclopedia Britannica, 1910

Garypus Litoralis

"Garypus litoralis, one of the Pseudoscorpiones. Dorsal view. I to VI, The prosomatic appendages. o,…

"Garypus litoralis, one of the Pseudoscopions. Lateral view. I to VI, Basal segments of the six prosomatic appendages. o, Eyes. prae-gen, Tergite of the prae-genital somite. I, Genital or first opisthosomatic. 2, 3, 10, The second, third and tenth somites of the opisthosoma. 11, The minute eleventh somite. an, The anus." &mdash; The Encyclopedia Britannica, 1910

Garypus Litoralis

"Garypus litoralis, one of the Pseudoscopions. Lateral view. I to VI, Basal segments of the six prosomatic…

"The true ticks attach themselves parasitically to the bodies of various mammals, as sheep, oxen, dogs, etc." &mdash; Williams, 1889

Harvest-tick

"The true ticks attach themselves parasitically to the bodies of various mammals, as sheep, oxen, dogs,…

"Holothyrus nitidissimus, one of the Acari; ater Thorell. A, Lateral view with appendages III to VI removed, I, plate covering the whole dorsal area, representing the fused tergal sclerites of the prosoma and opisthosoma; 2, similarly-formed ventral plate; 3, tracheal stigma. B, dorsal view of the same animal; II to VI, 2nd to 6th pairs of appendages. The 1st pair of appendages both in this and in C are retracted. C, Ventral view of the same; II to VI as in B; a, genital orifice; b, anus; c, united basal segments of the second pair of appendages; d, basal segment of the 6th prosomatic appendage of the right side. The rest of the appendage, as also of app. III, IV and V, has been cut away." &mdash; The Encyclopedia Britannica, 1910

Holothyrus Nitidissimus

"Holothyrus nitidissimus, one of the Acari; ater Thorell. A, Lateral view with appendages III to VI…

A young horseshoe crab or Limulus.

Horseshoe Crab

A young horseshoe crab or Limulus.

The itch mite (Sarcoptes) is a genus of skin parasites, and part of the larger family of mites collectively known as "scab mites". Adult scabies mites are spherical, eyeless mites with four pairs of legs. They are recognizable by their oval, ventrally flattened and dorsally convex tortoise-like body and multiple cuticular spines. Females are 0.30 to .45 mm long and 0.25 to 0.35 mm wide, and males are just over half that size.

Itch Mite

The itch mite (Sarcoptes) is a genus of skin parasites, and part of the larger family of mites collectively…

"Of the true mites, the domestic or cheese mite and the itch-mite are examples." &mdash; Williams, 1889

Itch-mite

"Of the true mites, the domestic or cheese mite and the itch-mite are examples." — Williams, 1889

"Koenenia Mirabilis, Grassi, one of the Palpigradi. A, Ventral view of prosoma and of anterior region of opisthosoma with the appendages cut off near the base; a and b, prosternites; c, mesosternite; and d, metasternite of the prosoma; f, ventral surface of the prae-genital somite; g, sternite of the genital somite (first opisthosomatic somite). B, Dorsal view. I to VI, prosomatic appendages; I, opisth, genital somite (first opisthosomatic somite). C, Lateral view, I to VI, prosomatic appendages; a, b, c, the three tergal plates of the prosoma; prae-gen, the prae-genital somite; 1 to 10, the ten somites of the opisthosoma. D, Chelicera." &mdash; The Encyclopedia Britannica, 1910

Koenenia Mirabilis

"Koenenia Mirabilis, Grassi, one of the Palpigradi. A, Ventral view of prosoma and of anterior region…

"Ventral surface of the entosternum of Limulus polyphemus, Latr. NF, neural fossa protecting the aggregated ganglia of the central nervous system; PVP, left posterior ventral process; PMP, posterior median process. Natural size." &mdash; The Encyclopedia Britannica, 1910

Limulus

"Ventral surface of the entosternum of Limulus polyphemus, Latr. NF, neural fossa protecting the aggregated…

"The remaining three pairs of mesosomatic appendages of Scorpio and Limulus. l130 indicates that there are 130 lamellae in the scorpion's lung-book, whilst l150 indicates that 150 similar lamellae are counted in the gill of Limulus." &mdash; The Encyclopedia Britannica, 1910

Limulus

"The remaining three pairs of mesosomatic appendages of Scorpio and Limulus. l130 indicates that there…

"Section through a portion of the lateral eye of Limulus, showing three ommatidia&mdash;A, B and C. hyp, The epidermic cell-layer (so-called hypodermis), the cells of which increase in volume below each lens, l, and become nerve-end cells or retinula-cells, rl; in A, the letters rh point to a rhabdomere secreted by the cell rl; c, the peculiar central spherical cell; n, nerve fibers; mes, mesoblastic skeletal tissue; ch, chitinous cuticle." &mdash; The Encyclopedia Britannica, 1910

Limulus

"Section through a portion of the lateral eye of Limulus, showing three ommatidia—A, B and C.…

"Section through one of the central eyes of a young Limulus. L, Cuticular or corneous lens. hy, Epidermic cell-layer. corn, Its corneagen portion immediately underlying the lens. ret, Retinula cells. nf, Nerve fibers. con. tiss, Connective tissue (mesoblastic skeletal tissue)." &mdash; The Encyclopedia Britannica, 1910

Limulus

"Section through one of the central eyes of a young Limulus. L, Cuticular or corneous lens. hy, Epidermic…

"Transverse section of a retinula of the lateral eye of Limulus, showing ten retinula cells (ret), each bearing a rhabdomere (rhab)." &mdash; The Encyclopedia Britannica, 1910

Limulus

"Transverse section of a retinula of the lateral eye of Limulus, showing ten retinula cells (ret), each…

"Diagram of a lateral view of a longitudinal section of Limulus. Suc, Suctorial pharynx. al, Alimentary canal. Ph, Pharynx. M, Mouth. Est, Entosternum. VS, Ventral venous sinus. chi, Chilaria. go, Genital operculum. br1 to br5, Branchial appendages. met, Unsegmented metasoma. Entap4, Fourth dorsal entapophysis of left side. tsm, Tergo-sternal muscles, six pairs as in Scorpio. VPM1 to VPM8, The eight pairs of veno-pericardiac muscles." &mdash; The Encyclopedia Britannica, 1910

Limulus

"Diagram of a lateral view of a longitudinal section of Limulus. Suc, Suctorial pharynx. al, Alimentary…

"Section through an early embryo of Limulus longispina, showing seven transverse divisions in the region of the unsegmented anterior carapace. The seventh, VII, is anterior to the genital operculum, op, and is the cavity of the praegenital somite which is more or less completely suppressed in subsequent development." &mdash; The Encyclopedia Britannica, 1910

Limulus Longispina

"Section through an early embryo of Limulus longispina, showing seven transverse divisions in the region…

"Diagram of the dorsal surface of Limulus polyphemus. oc, Lateral compound eyes. oc', Central monomeniscous eyes. PA, Post-anal spine. I to VI, The six appendage-bearing somites of the prosoma. VII, Usually considered to be the tergum of the genital somite, but suggested by Pocock to be that of the otherwise suppressed praegenital somite. VIII to XIII, The six somites of the mesosoma, each with a movable pleural spine and a pair of dorsal entopophysis or muscle-attaching ingrowths. XIV to XVIII, The confluent or unexpressed six somites of the metasoma." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"Diagram of the dorsal surface of Limulus polyphemus. oc, Lateral compound eyes. oc', Central monomeniscous…

"Ventral view of the posterior carapace or meso-metasomatic (opisthosomatic) fusion of Limulus polyphemus. The soft integument and limbs of the mesosoma have been removed as well as all the viscera and muscles, so that the inner surface of the terga of these somites with their entopophyses are seen. The unsegmented dense chitinous sternal plate of the metasoma (XIII to XVIII) is not removed." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"Ventral view of the posterior carapace or meso-metasomatic (opisthosomatic) fusion of Limulus polyphemus.…

"Third leg of Limulus polyphemus, showing the division of the fourth segment of the leg by a groove S into two, thus giving seven segments to the leg as in scorpion." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"Third leg of Limulus polyphemus, showing the division of the fourth segment of the leg by a groove…

"View of the ventral surface of the mid-line of the prosomatic region of Limulus polyphemus. The coxae of the five pairs of limbs following the chelicerae were arranged in a series on each side between the mouth, M, and the metasternites, mets. sf, The sub-frontal median sclerite. Ch, the chelicerae. cam, The camerostome or upper lip. M, the mouth. pmst, The promesosternal sclerite or chitinous plate, unpaired. mets, the right and left metasternites (corresponding to the similarly placed pentagonal sternite of Scorpio." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"View of the ventral surface of the mid-line of the prosomatic region of Limulus polyphemus. The coxae…

"The right coxal gland of Limulus polyphemus, Latr. a2 to a5, Posterior borders of the chitinous bases of the coxae of the second, third, fourth and fifth prosomatic limbs. b, Longitudinal lobe or stolon of the coxal gland. c, It's four transverse lobes or outgrowths corresponding to the four coxae." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"The right coxal gland of Limulus polyphemus, Latr. a2 to a5, Posterior borders of the chitinous bases…

"So-called "trilobite stage" of Limulus polyphemus. A, Dorsal; B, ventral view." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"So-called "trilobite stage" of Limulus polyphemus. A, Dorsal; B, ventral view." — The Encyclopedia…

"Ventral view of Limulus polyphemus. 1 to 6, The six prosomatic pairs of appendages. abd, the solid opisthosomatic carapace. tels, the post-anal spine (not the telson as the lettering would seem to imply, but only its post-anal portion). operc, the fused first pair of mesosomatic appendages forming the genital operculum." &mdash; The Encyclopedia Britannica, 1910

Limulus Polyphemus

"Ventral view of Limulus polyphemus. 1 to 6, The six prosomatic pairs of appendages. abd, the solid…

"Liphistius desultor, Schiodte, one of the Araneae Mesothelae. Dorsal view. I to VI, the prosomatic appendages; 4, 5, 6, the fourth, fifth and sixth tergites of the opisthosoma. Between the bases of the sixth pair of limbs and behind the prosomatic carapace is seen the tergite of the small prae-genital somite." &mdash; The Encyclopedia Britannica, 1910

Liphistius Desultor

"Liphistius desultor, Schiodte, one of the Araneae Mesothelae. Dorsal view. I to VI, the prosomatic…