620 



INDEX 



Magellaniinse, 301, 302. 



austral distribution of, 304. 

 defined, 308. 



development of, 293, 294. 

 median septum in, 296. 

 stages of growth in, 288, 303. 

 Magilus, attenuation in, 91. 

 Malacostraca, 114, 115, 202. 



affinities of trilobites to, 164. 

 Mammalia, accelerated development of 



spines in, 22. 



mammals, hollow-horned, horns for pro- 

 tection and offence in, 54. 

 mandibles of Triarthrus, 206. 

 Mannuopsis typica, 205. 

 Margaritiphora Jimbriata, spines in, 51. 

 Marsh, O. C., antlers as sounding- 

 boards, 54. 

 horns in two sexes of Protoceras, 58. 



on head of Triceratops, 54. 

 spines on tail of Stegosaurus, 54. 

 variations in direction of horns, 54. 

 Martinia, 231, 246. 

 Martinopsis, 246. 



Matthew, G. F., development of trilo- 

 bites, 310. 



metamorphoses of trilobites, 166. 

 protaspis stage of Microdiscus, 136. 

 stages of trilobites from Cam- 

 brian rocks of New Bruns- 

 wick, 171. 



small cephala of Ctenocepkalus 

 (Hartella) Matthewi and Cono- 

 coryphe (Bailielld) Baileyi, from 

 Cambrian of New Brunswick, 

 178. 



maxillae of Triarthrus, 206. 

 Meelcella, 245. 



Megalanteris, 246, 291, 305, 307. 

 Megalaspides, 146. 

 Megalaspis, 146. 

 Megathyriua?, 302. 

 defined, 308. 

 development in, 300. 

 Megathyris, 238, 246, 284, 300, 304, 

 308. 



decollata, labial appendages of, 279. 

 lophophore in, 275, 279, 280. 

 nodes and ridges on, and pedicle in, 



305. 



ptycholophus stage in, 284. 

 Megerlia, 238. 



Megerlina, 231, 246, 288, 294, 295, 303, 

 308. 



beginnings of primary loop in, 301. 

 development of, 295. 

 Jeffreysi, 299. 

 Lamarckiana, 295. 

 (=Muhlfddtia) truncata, 299. 

 megerliniform stage, 292. 

 Melo diadema, spiniform prominences 



on, 46. 



Menocephalus, 142. 

 Merista, 246. 

 Meristella, 246. 

 Maria, 377. 

 rectirostris, 372. 

 Meristellidae, fleshy portions of brachia 



in, 283. 

 Meristina, 246, 387. 



absence of embryonal sinus in, 388. 

 Maria, 314, 377, 388, 392. 

 beak in, 388, 389. 

 deltidial plates in, 390. 

 discussion of, 377. 

 triangular area in, 390. 

 nitida, 374. 

 rectirostris, 315, 378. 



absence of deltidial plates in 



adult, 261. 

 beak in, 389. 

 discussion of, 372. 

 embryo of, 377. 

 incipient stage in, 376. 

 Merostomata, 132, 184. 

 culmination of, 183. 

 eyes of some, 222. 

 included in Aspidonia of the Crus- 

 tacea, 112. 

 mesembryo, 121, 247, 248. 

 Mesokaulia, 242. 

 Mesonacis, 113, 142, 143, 144. 

 asaphoides, 177. 

 pygidium in, 143. 

 vermontana, 144. 

 Mesothyra, three spines in, 84. 

 Mesotreta, 244. 

 metagerontic stage, 248. 

 metastoma in Triarthrus, 209. 

 metembryo, 247, 248. 

 Metopias, 150. 



glabella in, 150. 

 Michelinia, 421, 424, 433. 

 buds in, 432. 



