GLOSSARY 447 



[Sperm atogem'ma] (0-Trep/na, seed ; gemma, bud), nearly equivalent to spermato- 



cyst. Differs in the absence of a surrounding membrane. [In mammals, LA 



VALETTE ST. GEORGE, 1878.] 

 Spermatogen'esis (<r7rfp/Aa, seed; yeVeo-ts, origin), the phenomena involved in 



the formation of the spermatozoon. Often used more specifically to denote the 



process of reduction in the male. 

 Spermatogo'nium (" Ursamenzelle ") (orTrep/xa, seed; yovrj, generation), the 



descendants of the primordial germ-cells in the male. Each ultimate sper- 



matogonium typically gives rise to four spermatozoa. (LA VALETTE ST. 



GEORGE, 1876.) 

 Spermatome'rites (o-Trep/xa, seed; /aepos, a part), the chromatin-granules into 



which the sperm-nucleus resolves itself after entrance of the spermatozoon. (In 



Petromyzon, BOHM, 1887.) 

 Sper'matosome (0-TrepjU-a, seed; oxo/xa, body), the same as spermatozoon. (LA 



VALETTE ST. GEORGE, 1878.) 

 Spermatozold (see Spermatozoon), the ciliated paternal germ-cells in plants. 



The word was first used by von Siebold as synonymous with spermatozoon. 

 Spermatozo'on (oWp/m, seed ; a>ov, animal), the paternal germ-cell of animals. 



(LEEUWENHOEK, 1677.) 

 Sperm-nucleus, the nucleus of the spermatozoon ; more especially applied to it after 



entrance into the egg before its union with the egg-nucleus. In this sense 



equivalent to the " male pronucleus " of Van Beneden. (O. HERTWIG, 



1875.) 



Sper'mocentre, the sperm-centrosome during fertilization. (FOL, 1891.) 

 Spi'reme (o-Trctp^/ua, a thing wound or coiled; a skein), the skein or " Knauel" 



stage of the nucleus in mitosis, during which the chromatin appears in the form 



of a thread, continuous or segmented. (FLEMMING, 1882.) 

 Spon'gioplasm (o-TroyycW, a sponge ; TrAaoywx, a thing formed), the cytoreticulum. 



(LEYDIG, 1885.) 

 Ste'reoplasm (crrepeos, solid), the more solid part of protoplasm as opposed to the 



more fluid " hygroplasm." (NAGELI, 1884.) 

 Substantia hyalina, the protoplasmic ground-substance or u hyaloplasm." 



(LEYDIG, 1885.) 

 Substantia opaca, the protoplasmic reticulum or "spongioplasm." (LEYDIG, 



1885.) 

 Synap'sis (o-vvaTrrw, to fuse together) . A stage in the nucleus preceding the first 



maturation-division, characterized by the massing of the chromatin at one side 



of the nucleus. From it the chromatin-masses emerge in the reduced number. 



(MOORE, 1895.) 

 Te'loblast (re'Aos, end ; /3Aacrro's, a germ), large cells situated at the growing end 



of the embryo (in annelids, etc.), which bud forth rows of smaller cells. (WHIT- 

 MAN, WILSON, 1887.) 

 Telole'cithal (re'Aos, end ; Ae/aflos, yolk), that- type of ovum in which the yolk is 



mainly accumulated in one hemisphere. (BALFOUR, 1880.) 

 Te'lophases, Telokine'sis (re'Aos, end), the closing phases of mitosis, during 



which the daughter-nuclei are re-formed. (HEIDENHAIN, 1894.) 

 To'noplasts (TWOS, tension ; TrAdo-rds, form), plastids from which arise the vacuoles 



in plant-cells. (DE VRIES, 1885.) 

 Trophoplasm (rpo^r;, nourishment ; TrActo^a) . I . The nutritive or vegetative 



substance of the cell, as distinguished from the idioplasm. (NAGELI, 1884.) 



2. The active substance of the cytoplasm other than the "kinoplasm " or archo- 



plasm. (STRASBURGER, 1892.) 

 Tro'phoplasts (Tpo4>rj, nourishment ; TrAao-rds, form), a general term, nearly equiv- 



