170 SEA-SIDE STUDIES. 



was led to question the function of the convohited 

 bands. Questioning, of course, meant something more 

 than supine doubt. I began on the 14th May to 

 examine closely into the evidence, and on the 12th 

 June I was fortunate enough to confirm all doubts by 

 the discovery of the real ovaries (such as they are) in a 

 large Crassicornis : here there were no thread-capsules, 

 but abundance of unmistakable ova, each with its " ves- 

 icle of Purkinje." The thrill of delight with which 

 the assurance broke upon me may be conceived.* At 

 that time I, of course, believed that the grape-like 

 cluster in which the ova were lying were true and 

 permanent ovaries ; but having since been frequently 

 unable to detect them in adult specimens, and never 

 in young specimens, I came to the conclusion that 

 these ovaries are temjporary organs, formed by an 

 accumulation of germ-cells in various parts of the free 

 border of the septa ; that, in fact, they represent the 

 first rudimentary state of what in higher animals be- 

 comes the special organ. This conclusion is, however, 

 purely theoretical, and I will now state what any one 

 may see who examines an adult fresh from the rock- 

 pool or tank. With a rapid but not deep incision we 

 lay open the envelope from the outside; the convoluted 



* I subsequently ascertained that Mr Teale and M. Hollard had de- 

 scribed these ovaries ; I only claim priority in the elucidation of their 

 structure and function, as temporary organs, similar to those of the 

 Hydra. [Since this was published, it has been found that the sexual 

 organs of the smaller Na'ids are also only temporary, and disappear 

 after the ova and spermatozoa are extended. — See Gegenbaur: Ver- 

 glelcliende Anaiomie, 1859, p. 183.] 



