28 Gen. Sub. 
GENERAL SUBJECTS. 
half its size. Germinal vesicle amoeboid in large, richly-equipped ova. 
“ Yolk nuclei *’ not from germinal vesicle, though arising near it, simply 
nutritive yolk concretions. 
Tessin, G. Ueber Eibildung und Entwicklung der Rotatorien. Z. 
wiss. Zool. xlvi, pp. 273-302, 2 pis. 
In describing maturation of ova, notes, inter alia , distinct traces of 
formation of polar cells. 
Thomson, J. A. Recent Researches in Oogenesis. Q. J. Micr. Sci. 
xxvi, pp. 591-606. 
Historical review of recent observations on polar bodies and follicular 
cells. 
Tichomiroff, A. [See Reproduction.] 
Comparison of analysis of ova of Bombyx mori before and after incu- 
bation. The ova lose in developing 7 per cent, of water and 3 per cent, 
solid material (principally glycogen and fat). 
Weismann, A. Richtungskorper bei parthenogenetischen Eiern. Zool. 
Anz. ix, pp. 570-573. 
Polar cells in Polyphemus oculus, Byotrephes longimanus, Moina para- 
cloxa , Baphnia longispina, &c. 
Wjelowiejski, II. v. Zur Keuutniss der Eibildung bei der Feuerwanze. 
Zool. Anz. viii (1885), p. 3G7. 
• . Zur Morphologie des Insectenovariums. Zool. Anz. ix, pp. 
132-139. 
Inter alia , corroboration of previous opinion that there is no transi- 
tion botwoen elements of terminal chamber and young ova. 
. Ueber die Ensteliung dor Dotterelemente ira Thierei. Tagebuch 
d. 4 Zusammenkunft poln. Naturf. u Aerzte Posen, p. 17. 
Will, L. Die Ensteliung dos Eies von Colymbetes fuscus, L. Z. wiss. 
Zool. xliii, pp. 329-368, 2 pis. ; J. R. Micr. Soc. vi, pp. 764 & 765. 
Colymbetes fuscus. Nucleus of primordial ovum gives rise to large 
daughter-nuclei — the nuclei of giant epithelial cells (yolk- or nutritive- 
cells). The follicular ovum is the primordial ovum after the loss of the 
daughter cells, . 
4 . Spermatogenesis. 
^Ballowitz, E. Zur Lehre von der structur der spermatozoon. Anat. 
Anz. i, pp. 363-376. 
^Bellonci, G. Sui nuclei polimorfi delle cellule seminali delle anfibi. 
Bologna : 1886. 
Benda, C. Samenentwicklung bei Saugethieren. Arch, Anat. Phys. 
1886, pp. 186 & 187 ; J. R. Micr. Soc. vi, pp. 209 & 210. 
Emphasizes the activity of the “foot-cell,” in division and retraction. 
Differs conspicuously from Merkel aud Sertoli, and agrees generally with 
v. Ebner and H. H. Brown. 
