610 



INDEX 



Derhya, 245. 



Deslongchamps, E., brachial supports 

 in Macandrevia cranium, Dallina septi- 

 gera, and Muhlfeldtia sanguinea, 406. 

 characters of pedicle-openings, 240. 

 classification of Brachiopoda, 290. 

 deltidium in brachiopods, 391. 

 development of the deltidium, 263. 

 of loop in Macandrevia cranium 

 and Dallina septigera, 292. 

 platidiform stage in Platidia, 298. 

 desmids, spine growth in, 42, 43. 

 Desmoncus pohjcanthus, leaf of, 89. 

 development of trilobites, 109. 

 Diaphanometopus, 155. 



pentamerous lobatiou of glabella in, 

 155. 

 diatoms, spine growth in, 43. 

 Diccelosia, King, 399. 

 Dicranogmus, 150. 



glabella in, 150. 

 Dicranograptus Nicholsotn, apertural 



spines on, 45. 

 Dicranurus, 113, 151, 152. 

 Dictyocephalites, 140. 

 Dictyonella, absence of embryonal sinus 

 in, 388. 



Capewelli, 336. 

 reticulata, 315, 388. 

 beak in, 388. 

 discussion of, 335. 

 Dictyospongia Conradi, 49, 50. 



prismatica, 50. 

 DictyospongidiB, progressive differentia- 

 tion of ornament in, Hall, 49. 

 Dictyothyris, 245, 305, 307. 

 Z)je/fasma, 245, 283, 291, 305, 307, 411, 

 412. 



brachial supports in, 276. 

 Centronella-Wke loop in, 281. 

 development of brachial supports 



in, 410. 

 loop in, 411, 413. 

 turgidum, brachidium in, 281. 



development of brachial sup- 

 ports in, 410. 

 loop in, 412. 

 Dielasmina, 307. 

 differentiation, specific, in Achatinellae, 



Hyatt and Verrill, 36. 

 Difflugia acuminata, spines on fundus of, 

 43. 



with spine from fundus, 44. 



constricta, spines in, 44. 

 variable form of, 43. 



corona, spines on fundus of, 43. 



globulosa, spherical shell of, 43. 



pyriformis, pear-shaped shell of, 43. 

 Dignomia, 243. 

 Dikelocephalinae, 145. 

 Dikelocephalus, 113, 142, 143, 145. 

 Dimerella, 245. 

 Dindymene, 153. 



glabella in, 154. 



pentamerous head axis in, 154. 



pygidium in, 223. 



spiuiform processes in, 78. 

 Dinobulus, 243. 



Dinocerata, no descendants of, 96. 

 dinosaur, Jurassic, suppressed first digit 



in, 85. 

 Dinosauria, gigantic Cretaceous, ex- 

 treme spiuosity in, 70. 



great horned, protective plates and 

 spines in, 54. 

 Diodon, 70. 



maculatus, protective spines in, 55. 

 Dionide, 137, 138, 220. 



determination of sutures in, Bar- 

 rande, 134. 



eye-spots lost in, 135. 

 Dipleura, 129, 154. 



glabella and pygidium in, 155. 

 Discina, 231, 244. 

 Discinida;, 287. 

 Discinisca, 231, 244, 247, 255, 268, 284. 



arms of, 276. 



difference in valves in, 234, 235. 



discoid form of shell in, 287. 



growth of spiral arms in, Miiller, 

 282. 



hinge-line lost in, 236. 



larval form of, Miiller, 246. 



outline and liinge in, 238. 



pedicle in, 235, 251. 

 -opening in, 241. 



protegulum in, 229, 234. 



recent, discoid form of shell in, 

 287. 



similar form in both valves in, 236. 



stages of development in, 265, 266. 



striata, 236. 



tentacles in, 275. 



of taxolophus in, 277. 



