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 ( aKpov. apex, o-co/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. ; AcKt^os, the yolk of an egg), having little or no yolk (applied 



to eggs). (Balfour, 1880.) 

 Alloplasma'tic (aAAos, ditferent). Applied to active substances formed by dit^er- 



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



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.) 

 Aniito'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 {afxcj^L, on both sides ; dar-^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/xyXov, starch: TrAao-ros, TrXdaaeLv. form), the colourless starch- 

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



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

 of the daughter-chromosomes. (Strasburger. 18S4.) 



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

 the egg). (Pfluger, 1883.) 



Antherozo'id. the same as Sperniatozoid. 



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

 Bexedex. 1883.) 



Archiam'phiaster (apxi- = first, + amphiaster), the amphiaster by which the tirst 

 or second polar body is formed. (Whit.al-vx, 1878.) 



Ar'choplasma or Archoplasm (dpx(^^V' a ruler) (sometimes written <7rc////>/<is///). 

 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 (dpprjv, male). The sperm-aster or attraction-sphere formed during the 

 fertilization of the ovum. (Hexkix(j. 1890.) 



As'ter (do-rr/p, a star), i. The star-shaped structure surrounding the centrosome. 

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

 Karyaster), (Flemmlxg, 1892.)] 



[As'trocoele] (dcTTrjp, a star: koiAo?. hollow), a term somewhat vaguely api)lied to 

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



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