GLOSSARY 339 



Nuclein, the chemical basis of chromatin ; a compound of nucleic acid and 

 albumin. (MiESCHER, 1874.) 



Nucleo-albumin, a nuclein having a relatively high percentage of albumin. 

 Distinguished from nucleo-proteids by containing paranucleic acid wliich yields 

 no xanthin-bodies. 



Nucleochylema (x^Aos, juice), the ground-substance of the nucleus as opposed 

 to that of the cytoplasm. ( Strasburger, 1882.) 



Nucleohy'aloplasma (see Hyaloplasm), the achromatic substance (linin) in 

 which the chromatin-granules are suspended. (Strasburger, 1882.) 



Nucleomi'crosomes (see Microsome), the nuclear (chromatin) granules as 

 opposed to those of the cytoplasm. (Strasburger, 1882.) 



Nu'cleoplasm. i. The reticular substance of the (egg-) nucleus. (Van 

 Benedex, 1875.) -• "^^^^ substance of the nucleus as opposed to that of the 

 cell-body or cytoplasm. (Strasburger, 1882.) 



Nucleo-pro'teid, a nuclein having a relatively high percentage of albumin. May 

 be split into albumin and true nucleic acid, the latter yielding xanthin-bodies. 



CEdematin {oihr]ixa, a swelling), the granules or microsomes of the nuclear ground- 

 substance. (Reixke. 1893.) 



O'ocyte (Ovocyte), (cJdi/. egg; Kt'ro?, hollow (a cell)), the ultimate ovarian egg 

 before formation of the polar bodies. The primary oocyte divides to form the 

 first polar bodv and the secondary oocyte. The latter divides to form the second 

 polar body and the mature egg. (Boveri. 1891.) 



Oogen'esis, Ovogenesis (wdv, egg; yeVeo-is, origin), the genesis of the egg after 

 its origin by division from the mother-cell. Often used more specifically to 

 denote tlie process of reduction in the female. 



Oogo'nium, Ovogonium (cJdi'. egg ; yovrj. generation), i. The primordial mother- 

 cell from which arises the egg and its follicle. (Pfluger.) 2. The descendants 

 of the primordial germ-cell which ultimately give rise to the oocytes or ovarian 

 eggs. (Boveri, 1891.) 



Ookine'sis (cJdi/, egg; KLvrjcn?. movement), the mitotic phenomena of the egg dur- 

 ing maturation and fertilization. (Whitman, 1887.) 



O'vocentre. the egg-centrosome during fertilization. (FOL. 1891.) 



Oxychro'matin (ofws, acid ; see Chromatin), that portion of the nuclear substance 

 stained by acid aniline dyes. Equivalent to -linin" in the usual .sense. 

 (Heidenhain, 1894.) 



Pangenesis (7r5s (Trai/-), all; yeVecrt?, production), the theory of gemmules, ac- 

 cording to which hereditary traits are carried by invisible germs thrown off by 

 the individual cells of the Ixidy. (Darwin. 1868.) 



Pangeas (ttSs (vrav-), all; -yei'T^?. producing), the hypothetical ultimate supra- 

 molecular units of the idioplasm, and of the cell generally. Equivalent to 

 gemmules, micellae, idioblasts. biophores. etc. (De Vries. 1889.) 



Panmeri'stic (-rrav. all; /aepo?. part), relating to an ultimate protoplasmic structure 

 consisting of independent units. See Pangen. 



Parachro matin (see Chromatin), the achromatic nuclear substance (linin of 

 Scliwarz) from which the spindle-fibres arise. (Pfitzner. 1883.) 



Parali'nin (see Linin), the nuclear ground-substance or nuclear sap. (ScHWARZ, 



1887.) 

 Parami'tome (see Mitome). the ground-substance or interfilar substance of pro- 

 toplasm, opposed to mitome. (Fle.m.mixc;. 1892.) 

 Paranu'clein (see Nuclein). the .substance of true nucleoli or plasmosomes. 

 Pyrenin of Schwarz. (O. Hertwtg, 1878.) Applied by Kossel to "nucleins'" 

 derived from the cytoplasm. These are compounds of albumin and paranucleic 

 acid which yields no xanthin-bodies. 



