"Blackberry knot gall common on the stems of the blackberry." —Davison, 1906

Blackberry Knot

"Blackberry knot gall common on the stems of the blackberry." —Davison, 1906

This illustration shows the male and female pupae in galls-enlarged.

Blastophaga

This illustration shows the male and female pupae in galls-enlarged.

Galls on leaf of rose. The location of a parasite is often marked by swellings of peculiar and fantastic or beautiful forms (galls) that grow on leaves and stems.

Gall

Galls on leaf of rose. The location of a parasite is often marked by swellings of peculiar and fantastic…

Galls on leaf of rose. The location of a parasite is often marked by swellings of peculiar and fantastic or beautiful forms (galls) that grow on leaves and stems.

Gall

Galls on leaf of rose. The location of a parasite is often marked by swellings of peculiar and fantastic…

Galls on stem of grape. The location of a parasite is often marked by swellings of peculiar and fantastic or beautiful forms (galls) that grow on leaves and stems.

Gall

Galls on stem of grape. The location of a parasite is often marked by swellings of peculiar and fantastic…

This spongy gall is found on various species of roses, and is produced by several insects as receptacles for their eggs. the larvae then feed upon the juices of the plant.

Gall

This spongy gall is found on various species of roses, and is produced by several insects as receptacles…

Gall on a grape cane

Gall

Gall on a grape cane

"This term, from the latting <em>gala</em>, the oak-apple, and <em>colo</em>, to inhabit, is applied to a tribe of insects which are almost exclusively vegetable feeders, which includes the well-known Gall-Insect, <em>Cynips gallae tinctoriae</em>. The females of these punture the leaves, buds, and other parts of plants and trees, depositing an egg in the wound, accompanied probably by some irritiating fluid, which causes a diseased growth in the part, and thus produces the excrescences known as <em>galls</em>." &mdash; Goodrich, 1859

Gall Insects

"This term, from the latting gala, the oak-apple, and colo, to inhabit, is applied…

"Woolly Oak-gall, produced by Cynips Quercus ramuli." -Lindley, 1853

Gall Wasp

"Woolly Oak-gall, produced by Cynips Quercus ramuli." -Lindley, 1853

"Galls on the leaf of an Ochnaceous plant." -Lindley, 1853

Galls

"Galls on the leaf of an Ochnaceous plant." -Lindley, 1853

The larvae of leaf-miners eat out the tissue of the leaves of elm between the lateral veins. This leaves the leaves with a seared appearance in spots.

Leaf-Miners' Galleries in Elm

The larvae of leaf-miners eat out the tissue of the leaves of elm between the lateral veins. This leaves…

Pictured are mite galls on maple. The galls are malformations or swellings caused by the insect.

Mite Galls on Maple

Pictured are mite galls on maple. The galls are malformations or swellings caused by the insect.

The term applied to the psychological theories of Gall and Spurzheim, founded upon 1, the discovery that the brain, as the organ of the mind, is not so much a single organ as a complex congeries of organs; and 2, observations as to the existence of a certain correspondence between the aptitudes of the individual and the configuration of his skull.

Phrenology

The term applied to the psychological theories of Gall and Spurzheim, founded upon 1, the discovery…

Pictured are phylloxera galls on chestnut. Insect larvae cause malformations or swellings of the leaves or twigs, known as galls.

Phylloxera Galls on Chestnut

Pictured are phylloxera galls on chestnut. Insect larvae cause malformations or swellings of the leaves…

"The maple spot gall, so common on the leaves of the red maple, is made by the fungus-gnat of the order Diptera." &mdash; Davison, 1906

Maple spot gall

"The maple spot gall, so common on the leaves of the red maple, is made by the fungus-gnat of the order…