GLOSSARY 



[Obsolete terms are enclosed in brackets.,. The name and date refer to the first use of the word- 

 subsequent changes of meaning are indicated in the definition.] 



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

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

 (FLEMMING, 1879.) 



A'crosome ( aKpoi/, apex, oxu/xa, body), the apical body situated at the anterior end 

 of head of spermatozoon. (LENHOSSEK, 1897.) 



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



Ale'cithal (d-priv. ; Ac'iado?, the yolk of an egg), having little or no yolk (applied 

 to eggs). (BALFOUR, 1880.) 



Alloplasma'tic (dAAos, different). Applied to active substances formed by differ- 

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

 and of muscle-fibrillae. 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/x<:', on both sides ; doT?/p, a star), the achromatic figure formed 

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



1877.) 



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

 (SCHWARZ, 1887.) 



Amy'loplasts (a/xvAoi/, starch ; TrAaoro's, TrAacrcreii/, form), the colourless starch- 

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



An'aphase (dvd, 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.) 



Aiitiierozo'id, the same as Spermatozoid. 



Anti'podal cone, the cone of astral rays opposite to the spindle-fibres. (VAN 

 BENEDEN, 1883.) 



Archiam'phiaster {ap\i = first, + amphiaster), the amphiaster by which the first 

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



Ar'choplasma or Archoplasm (apxw, a ruler) (sometimes written archiplasm'), 

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

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



Arrhe'noid (dppr/v, male). The sperm-aster or attraction-sphere formed during the 

 fertilization of the ovum. (HENKING, 1890.) 



As'ter (do-TT/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.)] 



[AVtroccele] (do-r^p, a star; KotAos, hollow), a term somewhat vaguely applied to 

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



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