44 Gen. Sub. 
I. GENERAL SUBJECTS. 
tells against exaggerating the importance of the chromatin. It is at first 
diffuse, but is gradually aggregated ; Bataillon & Kcehler (28). 
Imitation of karyokinetic figures: Radiations due to expansion of drops 
of alcoholic solution of shellac, &c., allowed to fall on a smoked surface 
of paper or glass ; Henking (229). 
Distribution of pigment-granules in karyokinesis ; Nusbaum (377). 
Significance of asymmetrical karyokinesis ; Strcebe (495). 
Intermediate bodies : Zwischenkorper ; Lustig & Galeotti (326), 
Mitosis : Hjbcker (209). — Mitosis in germinal zone of A scar is ; 
Wasielewski (528). 
When amitosis occurs in testis or ovary, or rudiment of either, it occurs 
either in temporary investing cells or in reproductive cells which degene- 
rate ; vom Rath (411). 
Amitotic division in mid-gut gland of crayfish ; Frenzel (172). 
6. Oogenesis, Spermatogenesis, Maturation, Fertilisation. 
a. The Ovum . 
Summary as to first stages in development; Born (50, 51). — Some 
general considerations re chromosomes, &c. ; Hermann (237). 
Yitelline body of Balbiani : This is a central body surrounded by a 
zone of protoplasm ; it arises from the germinal vesicle and occurs in 
the ova of animals of every class. In Vertebrates it generally disappears 
before the ovum is ripe ; in some Invertebrates it persists even in the 
embryo. Perhaps it and the nucleolar elements of the germinal vesicle 
correspond to the macronucleus of Infusorians ; IIenneguy (238) ; 
Julin (276). 
Oogenesis in Ophryotrocha : Ovarian cells become either nutritive or 
reproductive. There seems to be a sort of competition among the ova for 
association with the nutritive cells, which are in the minority ; Braem 
(57). — Nutritive cells and ova in Ophryotrocha ; KoRschelt (297). — 
Oogenesis in Styelopsis grossularia ; Julin (275). — Oogenesis in Cyclas ; 
Stauffaciier (489). 
The nucleoli of ova either contain the products of chromatio meta- 
bolism or are pulsating organs ; IlAiCKER (210, 211), see Cell, p. 43. 
Germinal vesicle ; Hascker (209). 
Development of germ-cells in Branchipnis, &c (1) Similarity of male 
and female cells ; the specific peculiarities are rather physiological 
adaptions than of morphological importance. (2) Derivates of the 
primary germ-cells become (a) by karyokinesis reproductive elements, (b) 
by akinesis the surrounding egg-case or sperm-fluid. (3) The division of 
the cells is intimately associated with the foam structure. An initial step 
of importance is the fusion of intra-nuclear globules ; Moore (358). 
Sex-cells, origin of, in Ctenopho'ra Samassa (448).— Amitosis in sex- 
cells; vom Rath (411).— Staining living sex-cells ; Waldner (523). 
Yolk-nucleus ; Hubbard (258). 
