BREEDING HABITS OF THE EARTHWORM 97 



The two worms meet and overlap one another to about one- 

 third to one- fourth of their lengths, with the heads facing in 

 opposite directions and the ventral sides in contact. They then 

 secrete quantities of viscous mucus, which forms a thick band 

 about the cliteller regions of their bodies. These mucous bands 

 surround both bodies and serve to bind the copulating individuals 

 tightly together. Each worm then acts as a male, giving off a 

 quantity of seminal fluid that is conducted along the grooves 

 to the seminal receptacles of the other, where it is picked up 

 and stored. After the worms have separated, the slime tube 

 which is formed by the clitellum of the worm is worked forward 

 over the body, collecting albumen from the glands of the ventral 

 side. As it passes over the fourteenth segment, it collects a few 

 eggs from the oviducts and then passes the ninth and tenth seg- 

 ments, where it receives spermatozoa from the seminal recepta- 

 cles where they have been stored up. The sperm then fertilizes 

 the eggs. The slime tube is gradually slipped off over the head, 

 closing up as though with a draw-string, as first its anterior end 

 and then its posterior end slips off over the sharp prostomium. 



This closed slime tube, with the fertilized eggs and nutritive 

 fluid which it contains, constitutes the cocoon. In this cocoon 

 the eggs develop directly into the young worms, which, when 

 ready to emerge, crawl out through one end of the cocoon after 

 the slime plug has been dissolved away. The cocoons vary in 

 size and shape, according to the species. The smallest are hardly 

 one millimeter in length, while the largest are as large as eight 

 millimeters ... In Lumbricus terrestris (commonly known as the 

 orchard worm, rainworm, and various other popular names), 

 the capsules are lemon-shaped, having an olive color. The num- 

 ber of eggs in the capsules of Helodrilus trapezoides is from 

 three to eight ; in those of Lumbricus terrestris it is from four to 

 twenty. All of the eggs of the Lumbricus terrestris become 

 fecundated and develop; on the other hand, in the capsules of 

 H. trapezoides one egg only, or rarely two or three, produce 

 embryos . . . The embryos escape as small worms in about two 

 to three weeks. 



Under favorable conditions, which means plenty of food, 

 moisture, and mild summer temperature, the domesticated earth- 

 worm will produce one of the lemon-shaped egg-capsules every 

 seven to ten days. The capsule (cocoon) may contain from 



