316 



INDEX. 



Dorsal vessel of Inswts, 213 

 Dorsibranchiata (Annelida), 



166 i see Errantia) 

 Dracnnculus, 153 

 Dreissena, 256 



Ecderon, 97 

 Echinococci, 146 

 Echinode-rmata, 121 ; general 

 characters of, 122 ; develop- 

 ment of, 122, 123 ; divisions 

 of, 123 ; distribution of, in 

 space and time. 138-141 

 Echinoidea, 122, 123 ; charac- 

 ters of, 124 ; test of, 124, 

 125; ambulacral system of, 

 12<) ; digestive system of, 

 127 ; families of, 128 ; dis- 

 tribution of, in space, 138 ; 

 in time, 140 

 Echinozoa, 121 (see Annu- 



loida) 



Echinorhynchus, 151 

 Echinus, 124, 126, 127 

 Echiurus, 160 

 Ectocyst, 236 

 Ectoderm, 66, 97 

 Ectosarc, 43, 53 

 Edriophthalmata, 177 ; cha- 

 racters and divisions of, 189 

 E'edone, 281 

 Elysia, 267 

 Elysiadce, 264, 267 

 Elytra, of Aphrodite, 167 ; of 



Coleoptera, 210 

 Emaiginula, 266 

 Enallostega, 50 

 Encephala (Mollusca), 251, 



258 



Enci'inus. 139 

 Enderon, 97, 102 

 Endocyst, 236 

 Endoderm, 66, 97 

 Endoplasts, 67 

 Endopodite, 174, 175, 176 

 Endosarc, 43, 53 

 Endostyle, 241 

 Entomostega, 50 

 Entomostraca, 177 ; charac- 

 ters of, 182 ; divisions of, 

 177, 183 

 Entozoa, 141 

 EozoiJn, 51 

 />hemeridce, 219 

 Ephyra, !H 

 Epidermis (of the shell of 



Mollusca'), 230 

 Epimera, 174 

 Epipodite, 176 

 Epipodium, 259 ; of Pteropoda 



268 ; of Cephalopoda, 271 

 Episterna, 174 

 Epistome, 237, 239 

 Epistylis, 62, 63 

 Epizoa, 177 ; characters of 



177, 178 



Errantia, 162 ; characters of 

 166 ; gemmation of, 167 

 development of, 167; dis- 

 tribution of, in time, 168 

 Eude/tdrium, 75 



