482 



INDEX OF SUBJECTS 



Oxychromatin, 38, 303; staining-reactions, 



Oxydation-ferments, 351. 



Oxytriiha, 342. 



Oyster, germ-nuclei, staining-reactions, 175. 



PaUaviiinia, reduction, 275. 



Paludiua, dimorphic spermatozoa, 141. 



Pangenesis, 12, 290, 431. 



Pangens, 291. 



Parachromatin, ^41. 



Paralinin, 41. 



Fii ra iikvIhj , mitosis, 94, 315. 



y'<7;-(?wa'(///w, mitosis, 91 ; conjugation, 224; 

 reduction, 277. 



Paranucleus, 163. 



Parthenogenesis, theories of, 281 ; polar 

 bodies in, 2S0. 



Pellicle, 54. 



Pentatoma, 271. 



Petroinyzon, fertilization, 192, 212. 



Phallusia, fertilization, 193, 212. 



Physa, fertilization, 193, 2IO, 212; reversed 

 cleavage, 368. 



Physiological units, 289. 



Pieris, spinning-gland, 37. 



Pigment-cells, 102. 



Pilularia, fertilization, 216. 



Pinus, reduction, 275. 



Planaria, regeneration, 394. 



Plant-cells, plastids, 52; membranes, 54; 

 mitosis, 82; cleavage-planes, 363. 



Plasma-stains, 335. 



Plasniocyte, 52. 



Plasmosome, 34. 



Plasome, 291. 



Plastids, 52; of the ovum, 133; of the sper- 

 matozoid, 143; conjugation of, 229. 



Plastidule, 291. 



Plastin, 41, 331. 



Pkurophyllidia, 78, 94. 



Podophyllum, 267. 



Polar bodies, 181 ; nature and mode of for- 

 mation, 235-240; division, 236; in par- 

 thenogenesis, 281. 



Polar rings, 156, 202, 



Polarity, of the nucleus, 36; of the cell, 55; 

 of the ovum, 378; determination of, 382. 



Pole-plates, 91. 



Pollen-grains, formation, 263-265. 



Pollen-tube, 218. 



Polyclades, cleavage, 416. 



Polyc/icerus, 276, 325. 



Polygordius, cleavage, 368. 



Polyspermy, 198; prevention of, 199. 



Polystomella, regeneration, 344. 



Polyzoiiiiiin , I59.» 



Porcellio, amitosis, 1 1 6. 



Predelineation, 398. 



Prefonnation (see Evolution). 



Pressure, experiments, 375, 410. 



Principal cone, lOl. 



/'r/s///(//ts, 338. 



Promorphology (see Cleavage, Ovum). 



Pronuclei, 202. 



Prophase, 65. 



Prosthecc)\rus, 213, 235, 256, 259, 306. 



Prosthiosto)itiiin, 212. 



Protamiii, 334. 



Proteids, 331. 



Prothalliuni, 264; chromosomes in, 275. 



Protoplasm, 4, 5, 17, 19; structure, 23,42, 



293; chemistry, 331. 

 Protoplast (see Plastid). 

 Pseudo-alveolar structure, 50. 

 Pseudo-reduction, 248. 

 Pteris, 253. 



Pteroirac/iea, germ-nuclei, 186, 205. 

 PtycJtoptera, spireme-nuclei, 35. 

 Pygiira, 165. 

 Pyrenin, 41. 

 Pyrenoid, 133. 

 Pyrrhocoris, 1 65, 248. 



Quadrille of centres, 210. 



Rat, spermatogenesis, 170. 



Reduction, general outline, 234; parallel 

 between the two sexes, 241 ; theoretical 

 significance, 243; detailed account, 246; 

 in plants, 263; Strasburger's theory of, 

 275; in unicellular forms, 277; by conju- 

 gation, 257; modes contrasted, 247. 



Regeneration, Weismann's theory, 406; in 

 frog-embryo, 409; nature of, 425, 427; 

 in coelenterates, 430; of lens, 433. 



Rejirvenescence, 179, 224. 



Kenilla, ovum, 132. 



Rhahdouema, amitosis, 1 15. 



Rhyuchelmis, fertilization, 192, 193, 212; 

 cleavage, 370. 



Rotifers, sex, 145. 



Sagitta, number of chromosomes, 184; pri- 

 mordial germ-cells, 146; germ-nuclei, 184; 

 spermaster, 191. 



Salamander, epidermis, 3; spermatogonia, 

 20; mitosis in, 71, 78; pathological mito- 

 sis, 98; leucocytes, 102; spermatozoa, 

 140 ; maturation, 259. 



