INDEX — GLOSSARY 



439 



Pierre formation, fossils from, 366, 267, 

 366 ; geologic age of, 266, 366. 



Pigeon, compared to Ichthyornis, 372 ; 

 gizzard of, 369. 



Pigs, 397; number of digits in, 328; 

 parasites in, 140, 141. 



Pikes, 348. 



Pill-bug, 306; enrollment of, 2gi. 



Piltdown man, Eoanthro pus dawsoni. 



Pinaceae, 71. 



Pincer, of crustaceans, 276, 2yQ. 



Pineal opening, in ostracoderms, 338 ; 

 in plesiosaurs, 356 ; in Stegocephalia, 

 352 ; in theromorph reptiles, 355. 



Pines, 73. 



Pinna (plu. pinnae), 46. 



Pinnate, furnished with pinnules or leaf- 

 lets, s^, 5Q- 



Pinnipedia, 381 ; evolution of, 381 ; 

 geologic range of, 381. 



Pinnules, of blastoids, 157 ; of crinoids, 

 161; of Pentremites, 158; of plants, 

 58, 64. 



Pin-worm, 141. 



Pisces, 339-349 ; see fishes. 



Pisiform, of cat, 327 ; of mammals, jp5, 



395 



Pistil, 76. 



Placenta, 335, 374, 377. 



Placental mammals, 373, 374, 377. 



Placenticeras, 264 ; P. intercalate, 266. 



Placoid, 341. 



Plagiaiilax, 378. 



Planaria, 140. 



Planktonic, drifting aimlessly, without 



power to direct a course, 89. 

 Planorbis, blood in, 242. 

 Plantain, 78. 

 Plant lice, 320. 

 Plants, 29-82 ; as indicators of climate, 



30; classification of, 32 ; distinguished 



from animals, 2, 29; evolution of, 31 ; 



food of, 29; preservation of, 31; 



reproduction of, 30 ; respiration of, 30. 

 Planula, 125. 

 Plasmodium, 95. 

 Plaster of Paris, use in restoring shape of 



organisms, 16. 

 Plastron, of turtles, 365, 366. 

 Platecarpus coryphceus, 367. 

 Platyhelminthes, 140; fossils of, 140; 



geologic range of, 409. 



Platystrophia, 199; P. lynx, 200, 200; 

 evolution of, 200; recapitulation in, 



2CX3. 



Plectoptera, 319. 



Pleistocene, 407. 



Pleistocene fossils figured, 348, 383, 

 388, 303, 3Q4, 395. 



Pleistocene mammals, extinction of, from 

 North America, 376. 



Pleopods, in crustaceans, 276, 27Q. 



Plesiosaurs, 356-358, 357 ; evolution in, 

 356 ; food of, 357 ; geologic range of, 

 356 ; habitat of, 356 ; production of 

 young, 356 ; stomach-stones of, 356. 



Plesiosaurus, 356. 



Pleura (plu. plurae), 286. 



Pleuracanthus, 342. 



Pleural, pertaining to the pleurae or sides 

 of the thorax. 



Pleural bones, in turtles, 366. 



Pleural ganglia, in gastropods, 237 ; ih 

 pelecypods, 221. 



Pleural lobes, in trilobites, 286, 287. 



Pleural spines, 295. 



PIeuropter>'gii, 341 ; fins in, 340. 



Pleurotomaria, 244. 



Pleurotomariidae, 244, 246. 



Plicated stage in Pecieti, 231, 231. 



Plications, 188, 201. 



Pliocene, 407. 



Pliocene fossils figured, 388, 393, 394, 



395- 

 Pliopitheciis, 400. 

 Plumatellites, 180. 

 Pneumatocyst, 113; in graptolites, 114, 



115- 



Podozamites, 66. 



Pollen, 56 ; germination of, 43. 



Polygyra albolabris, 230 ; blood in, 242 ; 

 sense of smell in, 242 ; sight in, 243. 



Polymastodon, 378. 



Polyplacophora, 208. 



Polyprotodonts, 378. 



Polyps, > French pouipe or polypus, the 

 common name for the Octopus in 

 France, applied to the coelenterate 

 individual because of a superficial 

 resemblance; feeding, 109, iii; in 

 corals, 123, 123; in Hydrozoa, 108, 

 109; in Sertularia, 108, 109; repro- 

 ductive, 109, no. III. 



Polypterus, 345. 



