GENERAL INDEX. 445 



of the British iiakcd-cyed iiiediisa>, 14; his views of the morphology of corbuloc and goiiangia, 



61, note ; his batliymetrical zones, 163. 

 Forel, liis researches in the deep fauna of the Lake of Geneva, 170. 

 Formula; of the genetic succession of zooids, 101 — 105. 

 Forskal figures a Clava, and gives the first good figures of liydroid medusse, 7. 



Gartner institutes the genus Coryne, 264. 



Ganeia nutans, its sporosac provided with rudimentary radiating canals, 296. 

 Gastrovascular canals, 33. 



Gegenbaur, his memoir on the medusrc ; his division of the medusw into Acraspeda and Craspedota, 

 16 ; his memoir on the alternation of generations in the Hydroida ; his outlines of comparative 

 anatomy, 17; his case of buds occurring in the cavity of the stomach in Cimina jtrolifcra, 84; 

 > his observations on the developTnent of eggs in Lizzia KoUUceri and in Oceania armata, 97. 



Geryonidre, their metamorphoses, 80 ; cartilaginous tissue in, 115, note ; lithocyst in, 142, note. 

 Glossocodon curyhia, Ilaeckel's account of its metamorphosis, 81. 



Gmclin, his edition of the ' Systema Natura;,' state of hydroid zoology at the time of its publication, 8. 

 Gonangium, 34 ; its nature; always associated with a hydrotheca, 47 ; development of, 74; aggregated 

 gonangia in Coppinia, 54; gonangium springing from within the hydrotheca in Syntliecium, \li'.K 

 ^^Gonangial hydranths of Halecium lialecinuin, 58. 

 Gemmaria imjilexa, its anatomy, 223 ; its remarkable planoblasts, 291. 



Gemmation, its various sites, 150 ; occasionally coexistent with sexual reproduction in the medusa, 150. 

 Genera of liydroids, characters employed in their limitation and diagnosis, 237. 

 Generation, 147. 



Generative elements, their origin, 148 ; a product of the endoderm, 149. 

 ! Genetic succession of zooids, fornuilse of, 101 — 105. 

 ;Geryonia, its direct development from the egg, 100. 

 Gonocheme, 29, 32. 



Gonophores, 29; gradations in their complexity, 43. 

 Gonosome, definition of, 23 ; general view of, 29. 

 Gonothyrsea, its meconidia, 55. 



Gosse, his observation of the development of the egg in Turris, 97 ; his account of Lar sahellarum, 42(). 

 Grant, Prof., his recognition of a polyzoal type in Flustra, 11. 



GraptoliteS; their tyi)ical form ; monoprionidian and diprionidian forms ; their probable affinities with 

 the Hydroida, 176; referred by authors to the calyptoblastic hydroids ; their rod or solid axis, 

 177 ; comparison of their rod with that of Rhabdopleura, 178 ; their callicles compared with the 

 nematopliores of the Plumularida;, 179 ; their affinities, both hydroidal and rhizopodal, 180 ; their 

 supposed gonangia as described by Hall, 181 ; and by Nicholson, 182 ; early stages of their deve- 

 lopment; various views of their nature, 183. 

 Green, Prof. J. R., his ' Manual of the Ccclenterata,' 18 ; his discovery of the Diplura medusa, 3.'->0. 

 Growth of the tissues dependent on cell-formation, 132. 

 Gubernaculum, 47. 



Gulf Stream, exploration of, by the United States Coast Survey, 165, note. 



Gymnoblastca, a sub-order of liydroids ; characters of this sub-order, 189 ; genera of Gymnoblastea pro- 

 bably for the most part limited in their geographical distribution, 160; synopsis of the families 

 and genera of the Gymnoblastea, 239. 

 Gymnophthalmia and Steganophthalmia, division of medusje into, by Forbes, 14. 



Haeckel, Ernst, his researches on the ^Eginidoe and Geryonidre, 19 and 80; his views as to 

 ' alleogenesis' considered, 106; his account of 'medusa cartilage,' \l^, note ; his researches on 

 the nervous system of the Geryonidte, 138; his observations on the lithocyst in the Geryonid<c, 

 142, note ; his view of the aboriginal type of the Hydroida, 230. 

 Halecium halecinum, its gonangial hydranths, 58. 

 Hensen, his account of the lithocvst, 141, note. 



Hincks, his 'History of British Hydroid Zoophvtcs,' xi, Prcf.; he describes Ophiodes and its peculiar 

 appendages, 28; his sub-orders of the Hydroida, 190, note; he demonstrates the identity of form 



