Chap. II. 



MORPHOLOGY AND NOMENCLATURE. 



87 



It has already hvon stated, tliat the communities of Diphyido3 ^ l)egin with a 

 Medusa {Fir/. 51), judging from the investigations of Gegenbauer detailed above 



F!ff. 51. 



Fi!j. 02. 



Fig. 53. 



Embryo of 



DlPHYES SlEBOLDII, Kijll. 



{ G'pled from Gegenbauer.) 



Remnant of the embryonal body. - 

 Swimming-bell developed from the e 

 bryonal body. 



Galeolaeia filieormis, Leuck. 

 Diphyes qiiadrivalvis, Gegenb. 

 {Qipiedfrom Gegenbauer.) 

 a b Anterior and posterior swimming- 

 bells. — c String of twia individuals. 

 — d Feelers with lasso cells. — e Ca^cjil 

 termination or base of the connecting 

 tube or axis of the community. 



Two twin individuals of the pen- 

 dent string of the community of 

 Diphyes Sieboldii, KiJll. 

 a a The so-called scales.— 6 b The so-called 

 Polyps. — yn The so-called sexual cap- 

 sule. — c External feeler, with lasso 

 cells. — d Feeler contracted. 



(pp. 5.3 and 54), and that from the first twin community, formed of two sterile Me- 

 du.sa3 {Fig. 52 a I), arise a string of similar twin communities {Fig. 52 c), consisting 

 of a medusoid Hydra {Fig. 53 a a) and a fertile sexuid Medusa {Fig. 5.3 ni), the 

 so-called Gonocalyx, dropping off together and living for a time as independent 

 beings, several of which have been described as distinct genera. 



If the views I have here presented of the nature of the Siphonophora^ are 

 correct, there is no need of a special nomenclature to describe the different indi- 

 viduals of their communities; and we shall hereafter deal with them as with differ- 

 ent kinds of Hydras and of Medustie, dcscri))ing successively their polymorphous 

 individuals as we would describe different genera and species of Hydroids and of 

 free Acalephs belonging to other flimilies of the class, and introduce only one new 

 element in these descriptions, on account of the different modes of association of the 

 many individuals united together in one and the same community, as it becomes 

 necessary here to allude to their various combinations. 



' Since the preceding pages were printed I have 

 received two interesting papers upon Diphyidaj and 

 Physophorid;e from their distinguished author, Dr. 

 C. Gegenbauer : Ueber Abjla trigona und deren 



Eudoxiernbrut, Jena, 4to. fig. ; and Neue Beitriige 

 zur nilhern Kenntniss der Siphonophoren ; separately 

 printed from the Act. Nov. Acad. Natur. Curios, 

 for the current year. 



