INDEX 



519 



Cyrtia, 505 ; stratigraphical distribu- 

 tion, 507, 608 

 Cyrtoceras, 394 

 Cyrtodaria, 457 

 Cyrtodonta, 452 

 CyrtoliUs, 407 

 Cyrtonotus, 448 

 Cyrtotoma, 414 

 Cysticopsis, 3-46-351, 441 

 Cystiscus, 435 

 Cystopelta, 325, 326, 440 

 Cytherea, 454, 454 



Dacrydium, 449 



Daedalochila, 441 



Dall, W. H., quoted, 35; on branchiae, 

 164 



Damayantia, 440 



Daphnella, 426 



Darbyshire, R. D.,on tenacity of life, 

 39 



Dardania, 415 



Dart-sac, 142 



Daudebardia, 289, 292 f., 44O 



Davidsonia, 505, 508 



Daiosonella. 410 



Dayia, 505, 508 



Decapoda, 385 f. 



Decollation, 260 



Deep-sea Mollusca, 374 



De Folin, experiment on Cyclostoma, 

 157 



Deianira, 4IO 



Delage, experiments on otocysts, 197 



Delphinula, 409 



Deltidium, 499 



Dendronotus, 433 ; protective colora- 

 tion, 72 ; habits, 51 



Dentalium, 6, 444, 445 ; used as money, 

 97 ; veliger, 131 ; radula^ 228 



Dentellaria, 350-355, 441 ; aperture, 63 



Desert species, 25, 85 



Deshayesia, 41I 



Desmoidea, 4^3 



Development of fertilised ovum. 130 f. 



Dexiohranchaea, 437 



Diadema, 414 



Diala, 415 



Dialeuca, 441 



Diaphora, 314 



Diaphorostoma, 412 



Diastema, 4I8 



Diastoma, 417 



Diaulula, 4^4 



Dibaphus, 425 



Dibranchiata, 380 ; eye, 183 ; nervous 

 system, 207 



Diceras, 269, 455 



Didacna, 12, 297, 455 



Differences of sex, 133 



Dignomia, 511 



Digonopora, 134, 144 



Diloma, 4O8 



Dimorphoptychia, 4IO 



Dimya, 450 



Dinobolus, 504, 508 



Dinoplax, 403 



Ditocardia, 9, 170, 405 t. 



Diplodonta, 452 



Diplommatina, 302-327, 413 



Diplomphalus, 322, 323, 440 



Diplopoma, 346, 351, 414 



Dipsaccus, 424 



Dipsas, 307 



Discina, 464, 468, 471, 475, 487 ; distri- 

 bution, 485 ; fossil, 493, 504 ', strati- 

 graphical distribution, 506, 508 



Discinidae, 4S7, 496, 504, 0O8, 511 



Discinisca, 487, 510 ; distribution, 485, 

 486 



Discites, 395 



Discodoris, 434 



Discosorus, 394 



Distortio, 255 — see Persona 



Ditropis, 312, 314, 414 



Docoglossa, 227, 405 



Dolabella, 428, 431 



Dolabrifer, 431 



Dolium, 419 ; acid secretion, 237 



Donax, 269, 446, 453 



Dondersia, 404 



Dorcasia, 333, 441 



Doridium, 430 



Doridunculus, 434 ; radula, 229 



Doriopsis, 434 



Doris, breathing organs, 159 ; radula, 

 230 



Dorsanum, 423 



Dosidicus, 390 



Dosinia, 454 



Doto, 433 ; protective coloration, 71 



Dreissensia, 14, 123, 452 ; hibernation, 

 26 ; singular habitat, 48 ; veliger, 

 132, 146 ; eyes, 192 



Dreissensiomya, 452 



Drepania, 434 



Drillia, 426 



Drymaeus, 356, 442 



Dryptus, 356, 441 



Durgella, 301, 304, 440 



Dwarf varieties, 88 



Dybowskia, 290 



Eastonia, 454 



Eburna, 267, 424 ; radula, 220 



Ecardines, 466 ; muscles, 476 ; fossil, 



493 ; families, 4S7, 503, 508 

 Eccyliomphalus, 413 

 Echinospira, 133 

 EdenUilina, 338 

 Egg-laying of Arion,i2 i.; of Mollusca 



generally, 123 

 Eglisia, 4II 

 Eider-duck, shells used by, 102 



