22 Gen . Sub. 
GENERAL SUBJECTS. 
Henking, H. Untersuchungen fiber die ersten Entwicklungsvorgiinge 
in den Eiern der Insekten. u. Ueber Spermatogenese und deren 
Beziehung zur Eientwicklung bei Pyrrhocoris apterua , L. Op. cit. li, 
pp. G85-736, 3 pis., 1 fig. 
Primordial sperm-cells correspond to primordial ova ; both contain 
24 chromosomes; the spermatocytes of the first order correspond to 
immature ova ; the formation of polar bodies corresponds to the two 
divisions of spermatocytes, in both there is a “ reduction-division/ 
Details as to minute structure of the spermatosoma. 
Hermann, F. [See “ Cell and Protoplasm/'] 
Jordan, E. O. The Spermatophores of Diemyctylus, J, Morph, v, 
pp. 263-270. 
Lode, A. Untersuchungen Liber die Zahlen- und Regen erations-Yerlnilt- 
nisse der Spermatozoiden bei Hund und Mensch. Arch. ges. Phys. 
xv, pp. 278-292. 
* . Ueber Spermaproduktion beim Menschen und beim Hunde. 
Wien. med. Blatter, xiv, pp. 754 & 755. 
Maddock, It. L. Some observations of the various forms of human 
Spermatozoa. J. E. Micr. Soc. 1891, pp. 1-5, 1 pi. 
Meves, F. Ueber amitotische Kernteilung in den Spermatogonien des 
Salamanders und Yerhalten der Attraktionssphiire hei derselben. 
Anat. Anz. vi, pp. 626-639, 11 figs. 
Monticelli, F. S. Della spermatogenesi dei Trematodi. Boll. Soc. 
Nat. Napoli, v, pp. 148-150. 
Pictet, C. Recherches sur la spermatogenese chez quelques Invertebres 
de la M5diterran6e. MT. z, Stat. Neap, x, pp. 75-152, 3 pis. ; also 
Leipzig ; 8vo, 83 pp., 3 pis. 
Description of spermatogenesis of 5 Ecliinoids, a Siphonophore, a 
Pteropod, a Cephalopod, a Polyclnete ( Eteone) } and Salpci virgula. The 
nucleus of the spermatide forms the head of the spermatozoon ; the 
nucleus proper is dissolved in karyoplasma, its apparent structure is a 
post-mortem appearance, but after the penetration of the spermatozoon 
into the ovum, a definite structure is assumed. The tail is formed from 
cytoplasm. The accessory nucleus is an eliminating! corpuscle ; in Eteone 
it is detached from the cell, in Siplionophom it persists by the side of the 
nucleus ; in most Echinoids it forms the median segment of the sperma- 
tozoon. 
Ratii, 0. v. Ueber die Bedeutung der amitotischen Kerntheilung im 
Hoden. Zool. Anz. xiv, pp. 331, 332, 342, 343, 355-363, 3 figs. 
Spermatogenesis proper in Astacus, &c., occurs solely by mitosis. 
Amitotic division is restricted to the marginal Stiitzzellen. 
Russo, A. Ricerclie sulla distruzione e sul rinnovamento del parenchima 
ovarico nelle Ophiurece. T. c. pp. 50-59, 15 figs. 
