GLOSSARY 



[Obsolete terms are enclosed in brackets. Tlie name and date refer to the first use of the word; 

 subsequent changes of meaning are indicated in the detinition.] 



Achro'matin (see Chromatin), the non-staining substance of the nucleus, as 



opposed to chromatin ; comprising the ground-substance and the linin-networlv. 



(Flemming, 1879.) 

 A'crosome ( aKpov, apex. awfm. body), the apical body situated at the anterior end 



of head of spermatozoon. (Lexhossek. 1897.) 

 [Akaryo'ta] (see Karyota), non-nucleated cells. (Flemming, 1882.) 

 Ale'cithal (d-priv. : Acht^os. the yolk of an egg), having little or no yolk (applied 



to eggs). (Balfour. 1880.) 

 Alloplasma'tic (aAAo?. ditTerent). Applied to active substances formed by ditfer- 



entiation from the protoplasm proper, e.g: the substance of cilia, of nerve-fibrills, 



and of muscle-fibrillas. Alloplasmatic organs are opposed to •* protoplasmatic," 



which arise only by division of preexisting bodies of the same kind. (A. Meyer, 



1896.) 

 Amito sis (see Mitosis), direct or amitotic nuclear division; mass-division of 



the nuclear substance without the formation of chromosomes and amphiaster. 



(Flemming, 1882.) 

 Am'phiaster (d|Li<^!,', on both sides ; dcrTi/p, a star), the achromatic figure formed 



in mitotic cell-division, consisting of two asters connected by a spindle. (FoL, 



1877-) 

 Amphipy renin (see Py renin), the substance of the nuclear membrane. 



(SCHWARZ, 1887.) 



Amyloplasts (afxyXov. starch : TrAacrro's. TrAao-o-etv. form), the colourless starch- 

 forming plastids of plant-cells. (Ekrera, 1882.) 



An'aphase (avd, back or again), the later period of mitosis during the divergence 

 of the daughter-chromosomes. (Strasburger. 1884.) 



Aniso'tropy (see Isotropy), having a predetermined axis or axes (as applied to 

 the egg). (Pfluger, 1883.) 



Antherozo'id. the same as Sperniatozoid. 



Antipodal cone, the cone of astral rays opposite to the spindle-fibres. (Van 

 Beneden. 1883.) 



Archiamphiaster (dpx^ = ^I'st, + amphiaster), the amphiaster by which the first 

 or second polar body is formed. (Whitman, 1878.) 



Ar choplasma or Archoplasm (apx^^v- a ruler) (sometimes written archiplastji), 

 the substance from which the attraction-sphere, the astral rays, and the spindle- 

 fibres are developed, and of which they consist. (Boverl 1888.) 



Arrhe'noid (appr;v. male). The sperm-aster or attraction-sphere formed during the 

 fertilization of the ovum. (Henking. 1890.) 



As'ter (d(TT7;p, a star), i. The star-shaped structure surrounding the centrosome. 

 (FoL. 1877.) [2. The star-shaped group of chromosomes during mitosis (see 

 Karyaster). (Flemming, 1892.)] 



[As'trocoele] {a(ny]p, a star; koZAos, hollow), a term somewhat vaguely applied to 

 the space in which the centrosome lies. (FoL, 1891.) 



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