COCOONS OF ALLOLOBOPHORA FCETIDA. 2O? 



stage of development, 2, 3, 4, and even 10 or 12 cells. When 

 the stage of any egg appeared doubtful, it was fixed, stained 

 and mounted for examination. Any cocoons in the compost 

 before it was put in the bowls would have had a start in de- 

 velopment of at least three days --so it was practically im- 

 possible to mistake them for the cocoons laid by the isolated 



worm. 1 



Twenty worms were isolated for the experiments described, 

 and of these, one worm deposited ten cocoons at average in- 

 tervals of three days. This worm was vivisected six days after 

 depositing the tenth cocoon, and all four spermathecse were 

 found to be about one quarter full. The clitellum-- which was 

 very pronounced when the worm was isolated had entirely dis- 

 appeared, and the seminal vesicles appeared abnormal --they 

 were a brownish-yellow, and quite different in appearance and 

 texture from those of worms captured in the compost heap. 

 This pathological condition, undoubtedly due to confinement, 

 may have prevented the deposition of cocoons continuing until 

 the contents of the spemathecae was exhausted. 



Of the remaining nineteen worms, one deposited four cocoons, 

 and one deposited three, within fifteen days ; one worm deposited 

 three in nineteen days ; two deposited two within seven days, and 

 two deposited two within eight clays. Three worms deposited 

 each one cocoon on the third day, one worm deposited one on 

 the fourth day, and one deposited one on the fifth clay. In 

 some of these cases the experiment was cut short by the escape 

 of the worm. 



Seven of the nineteen worms deposited no cocoon, vivisection 

 showing, however, that two of them were pathological, and that 

 the spermathecse of four of them were almost empty. We found 

 the spermathecae full, and the seminal vesicles normal in only 

 one of the"se worms, and there was no apparent cause why this 

 worm should not deposit cocoons. These worms were isolated 

 from thirteen to twenty days before vivisection. 



The experiments described above establish the fact that a 



1 In order to become perfectly familiar with the different stages of development 

 possible within three days, we preserved a large number of fresh cocoons, opening 

 them at intervals of three hours, and fixing, staining and mounting the eggs. 



