The earthworm.

Earthworm

The earthworm.

"Lumbricus agricola. A, entire specimen, lateral view; B, ventral view of anterior portion of the body, magnified. 1, 15, 33, first, fifteenth, and thirty-third segments. The black dots represent the setae." -Parker, 1900

Lumbricus Agricola

"Lumbricus agricola. A, entire specimen, lateral view; B, ventral view of anterior portion of the body,…

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.…