SPAWNING HABITS OF CH.ETOPLEURA APICULATA. 243 



VII. 



July 6-8 : 



100 Chitons collected July 6. 



ist night, several specimens spawned about 10 P.M., and 



a few more after i A.M. 



2d day, several females spawned between 9 and 10 A.M., 

 July 8, and one or two continued at intervals "during 

 the afternoon ; spermatozoa also abundant. ^ Begin- 

 ning about 5 P.M., many females (35-40) spawned 

 in great abundance, laying 2,000-2,500 eggs each. 



Note. July 8 seemed to be the height of the spawning season. 

 Spawning occurred day and night, practically all night and more or 

 less during the entire day. Spawning during the day not seen 

 before. 



* Last Quarter, July 8. 



Note. Experiments so far show that females spawn at the 

 approach of full moon, a few days before. Spermatozoa are shed 

 for longer periods and more readily than the eggs. Spermatozoa 

 appear in clouds very soon after animals are placed in quite water, 

 5-10 minutes, and sometimes continue nearly all night. Females 

 sometimes spawn the first night after collecting, but more abun- 

 dantly the second night. 



VIII. 

 July 11-14: 



100 specimens collected July n. 



ist night, several specimens spawned. 

 2d night, no eggs. 



3d night, several specimens spawned. 

 4th night, several specimens spawned. 



Note. This group was not well cared for, because attention was 

 necessarily diverted to other matters. There was considerable if 

 not abundant spawning, although not comparable to that of July 8. 



* New moon, July 15. 



IX. 



July 17-18: 



100 specimens collected July 17. 



ist night, two specimens spawned. 



