GENERAL INDEX. 443 



Clava, restoration of Gmelin's genus by Johnston, 243. 



Clava sqiiamosa, its peculiar liydrorhiza, 245; development of ovum in, 245. 



Clavatdla jirolifcra, ambulatory gonophore of, 30; anatomy of, 212; structure of its jjlanoblasts, their 



development and gemmation, 213 ; its planoblasts compared with an ordinary hydroid medusa, 



215; distinct from Eleutheria, 384; its discovery by Hincks, 385. 

 Climacograptus, a genus of Gra])tolites, 176. 

 Codonostome, 33. 

 Coeleuterata, establishment of this group by Leuckart, 15 ; manual of, by Greene, 18 ; homologies of, 



192; Kowalewsky's and Semper's views of the body-cavity of, 193, note. 

 Ccenosarc, 26. 

 Cohn, his comparison of the green matter of Hydra with that of Infusoria and with the chlorophyllc of 



plants, 135. 

 Coloured matter in the Hydroida, a secretion, 134. 



Contractility in the Hydroida dependent on fibrillated tissue and on simple sarcode, 136. 

 Coppinia arcta, its structure, 55. 

 Corals, animality of, demonstrated by Peysonelle, 5 ; tabulate and rugose corals, the hydroid nature of 



these maintained by Agassiz, 3, note, and 17. 

 Coralline zone, its hydroid fauna and associated \egetation, 168. 

 Corbula, its structure and development, 60 ; consists of a special and excessive development of the 



nematophoral system, 181, note. 

 Cordyhphora lacustris, conversion of its spadix into a hydranth, 204 ; account of its structure by Schultze, 



228 ; its fresh-water habitats ; probably an introduced species ; a light-shunning animal, 253. 

 Corydendrhan paras/tiotm, egg-like bodies described by Cavolini in its hydrocaulus, 263. 

 Corymorpha, development of the planoblast in, 77 ; canalliculation of endoderm in, 125; probable spon- 

 taneous fission in, 153 ; its anatomy, 208; structure of its stem, 209 ; its hydrorhizal filaments, 



209; structure of its hydranth, 209; its planoblasts, 210 ; its free frustules, 211 ; its medusa 



generically identical with the Steenstrupia of Forbes, 390. 

 Coryne, revision of the genus by Sars, 242; provisional and indeterminable species of, 271. 

 Corynoides, description of, by Nicholson ; no evidence of its hydroid affinity, 172. 

 Corynopsis, its planoblasts identical in form with those of Bougainvillia, 354. 

 Cosmopolitan species of Hydroida, 160. 

 Craspedota of Gegenbaur, 16. 

 Ctenophora, diagnostic characters of, 188 ; compared with hydroid medusa, 197 ; an order of Hydrozoa, 



and not of Actinozoa, 199. 

 Cunina octonaria, M'Crady's account of its metamorphosis, 81. 



Cunina KolUkeri, Fritz Muller's account of budding from the internal surface of the stomach, 83. 

 Ctmina prolifera, Gegenbaur's account of buds in cavity of stomach, 84. 

 Cunina, its direct development from the egg, 100. 

 Cuvier, institutes his primary group lladiata ; defects of this group, 9 ; his publication of the ' Regne 



Animal' and establishment of the class Acalepha, 10; recognises the difference of structure 



between the Actinozoal and the Hydrozoal types, 10. 

 Cystoseeia, zone of, 304, note. 



Dalyell, Sir J. Graham, his observations on the development of medusfc from hydroid trophosomes, 15; 



he describes the decapitation and re-formation of hydranths in Tubularia, 69. 

 Decapitation, spontaneous, and re-formation of hydranths in Tubularia, 69; the re-forniation of the 



hydranths a process of metamorphosis, 70. 

 Deep-sea zone, its hydroid fauna, 169. 

 Dendritic form, a result of gemmation, 67. 

 Development, a department of morphology, 66 ; development of the bud and of the cuibryo compared, 



66 ; development of the hydranth in the Gymnoblastea, 68 ; in the Eleutheroblastea, 60 ; in the 



Calyptoblastea, 71 ; embryonal development, 85. 

 Dicorijne conferta, locomotive sporosac of, 31 and 226; anatomy of Dicoryne conferia, 226; its piano- 



