ClipArt ETC
This diagram shows a fresh-water annelid. a, appendages; br., brain; d, dissepiments; i, intestine; m, mouth; nph, nephridium; oe, aesophagus; p, pavilion, line with ciliated entoderm; ph., pharynx; pr., processes from the anal segment; z, zone immediately in front of the anal segment where new segments are continually being formed; z', the zone of fission or budding. This takes place in the middle of a segment. The anterior half-segment of z' will produce a region like z for the anterior half of the worm.

Annelid

This diagram shows a fresh-water annelid. a, appendages; br., brain; d, dissepiments; i, intestine;…

This diagram shows a transverse section of dero. c., caelom; c.l., cells of the so-called "lateral line"; d.m., dermo-muscular wall including muscles and skin; d.v., dorsal blood vessel; ect, ectoderm; ent, entoderm; g, gut; g.f., giant nerve fibers; gl, glandular cells assisting in digestion; m.c., circular muscle fibers; m.l., longitudinal muscle fibers; n, nephridium; n.v., ventral nerve chain, made up of nerve cells and nerve fibers; s, setae; v.v., ventral blood vessel.

Annelid

This diagram shows a transverse section of dero. c., caelom; c.l., cells of the so-called "lateral line";…

"Transverse section of earthworm. A., Cuticle; B., epidermis; C.M., circular muscles; L.M., longitudinal muscles; D., a seta; C., coelom; Y.C., yellow cells; F., typhlosole; V.V., supra-neural blood vessel; S.V., sub-neural vessel; D.V., dorsal vessel; P., peritoneum; E., cavity of gut; G., endodermic lining of gut; N., part of a nephridium; R., opening of a nephridium; I., the nerve-cord; J., a nerve given off; K., giant fibres in the nerve-cord." -Thomson, 1916

Earthworm

"Transverse section of earthworm. A., Cuticle; B., epidermis; C.M., circular muscles; L.M., longitudinal…

"Dissection of lob-worm from dorsal surface. m., Opening of retracted buccal cavity; i., gullet; gl., diverticula on first diaphragm; gl''., oesophageal glands; d., dorsal blood vessels; ef1., first efferent branchial; g., stomach intestine; n6., sixth nephridium; ef 13., thirteenth efferent branchial; af13., thirteenth afferent branchial; a., anus; af1., first afferent branchial; h., heart of left side." -Thomson, 1916

Lob Worm

"Dissection of lob-worm from dorsal surface. m., Opening of retracted buccal cavity; i., gullet; gl.,…

"Ideal mollusc. m., Mouth; g.c., cerebral ganglia; c., edges of mantle skirt; z.g., duct of right lobe of digestive gland; s., pericardial cavity; f., edges of shell-sac; v., ventricle of heart; u., nephridium; an., anus; n., posterior part of the foot; l., opening of nephridium; k., genital aperture; g.ab., abdominal ganglion on visceral loop; g.v., visceral ganglion; z.l., left lobe of digestive gland; p., foot; g.pe., pedal ganglion; g.pl. pleural ganglion." -Thomson, 1916

Mollusc Parts

"Ideal mollusc. m., Mouth; g.c., cerebral ganglia; c., edges of mantle skirt; z.g., duct of right lobe…

This illustration shows a representation of the circulation of the blood, in its essential features. The arrows indicate the course of the blood. a, arteries; aur., auricle or receiving portion of the heart; d, digestive tract; c. d., capillaries of the digestive tract; c.r., capillaries of the respiratory organs; c.s., capillaries of the system; va., valves; ve, veins; vt, ventricle.

Nephridium

This illustration shows a representation of the circulation of the blood, in its essential features.…

A diagram of of the nephridium of Nereis. Nereis is a genus of polychaete worms in the family Nereidae. It comprises many species, most of which are marine, including the sandworm (Nereis virens) and the common clam worm (Nereis succinea). Nereis possess setae and parapodia for locomotion. They may have two types of setae, which are found on the parapodia. Acicular setae provide support. Locomotor chaetae are for crawling, and are the bristles that are visible on the exterior of the polchaeta.

Nereis

A diagram of of the nephridium of Nereis. Nereis is a genus of polychaete worms in the family Nereidae.…

"Dissection of Peripatus. at., Antennae; or.p., oral papillae; c.g., cerebral ganglia; sl.d., duct of slime gland (sl.g.); s.o.8, eighth segmental organ or nephridium; v.c., ventral nerve connected by transverse commissures (co.) with its fellow; s.o.17, seventeenth nephridium; g.o., genital aperture; A., anus; p.d.c., posterior commissure; F.17, seventeenth appendage; a.g., last crural gland--that of the opposite side is marked v.g.; F.1, F.2 first and second legs; oe.co., osophageal nerve commisure; oe., oesophagus; ph., pharynx--the remainder of he gut is removed." -Thomson, 1916

Peripatus Dissection

"Dissection of Peripatus. at., Antennae; or.p., oral papillae; c.g., cerebral ganglia; sl.d., duct of…