54 CORYNIDzE. 



GONOPHORES somewhat globular, borne amongst the 

 tentacles, or immediately below them. 

 GONOZOOID. UMBRELLA (at the time of liberation) globular, 

 destitute of thread-cells, with 4 interradial furrows; 

 MANUBRIUM extending to about the middle of the um- 

 brella, subcylindrical ; MARGINAL TENTACLES springing 

 from bulbous bases, bearing a prominent dark ocellus, 

 nodulated with clusters of thread-cells, and terminating 

 in a spherule. 



THIS species is the subject of an elaborate memoir by 

 Agassiz, in which he has treated its history exhaustively. 

 He has also fully described the adult gonozooid in a sepa- 

 rate paper. Wright had previously discovered the species 

 in Scotland, but had only met with it in the depauperated 

 condition which, according to Agassiz's observations, it 

 assumes towards the close of the breeding-season. He 

 describes his Coryne mirabilis as producing in the early 

 part of the year free gonozooids that resemble the Sarsia 

 of authors, while later on (April or May) these disappear, 

 and their place is taken by medusiform bodies of a differ- 

 ent shape, which probably in most cases continue fixed, 

 and mature their generative elements in situ. And this 

 change in the reproductive zooid is usually accompanied 

 by the degeneration and sometimes total disappearance 

 of the polypites. In this stage of the life-history, the 

 gonozooids are imperfectly developed. They are elongate- 

 ovate or cylindrical in form, generally with four small 

 bulbs instead of tentacles, and a manubrium inflated by 

 the mass of ova or spermatozoa, so as almost to fill the 

 cavity of the bell. Occasionally the tentacles are developed, 

 but " they have a stiff, jagged, and awkward appearance." 

 Some of these abnormal zooids have " a withered arid 

 wrinkled look," and probably cast their products in situ 

 and then perish. Others exhibit vigorous movements, and 



