ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
495 
Development of Diaphragm and Liver in the Rabbit.* * * § — M. A. 
Brachet has investigated the development of these organs in the rabbit. 
He finds that the diaphragm may be divided into two parts, one anterior, 
vertical, and transverse, and one posterior, dorsal, and oblique. Both 
of these, from the point of view of their origin, may again be divided 
into two parts. He looks upon the liver as formed of three principal 
lobes, the median, the left lateral, and the right lateral, in addition to 
which there are two secondary lobes. This is a view of the origin of 
the liver which is not generally taken, but the author gives facts in 
support of his view. 
Accessory Glands of the Thyroid Region.j — Hr. M. Jacoby finds, 
from a study of cat embryos, (a) that the external epithelial bodies 
associated with the thyroid arise from the cranial portion of the thymus ; 
( b ) that the internal epithelial bodies arise from the thyroid itself ; and 
(c) that the “ glandula carotica ” does not arise from epithelium, is not 
morphologically a gland, and has primarily nothing to do with either 
thyroid or thymus. The carotid gland begins as a connective thickening 
of the adventitia of the common carotid in the region of its division, 
and gradually increases in vascularisation. 
Spermathecse and Fertilisation in American Urodela.f — Dr. B. E. 
Kingsbury finds spermathecse containing spermatozoa on the dorsal wall 
of the cloaca of the females of Necturus , Amblystoma, Diemyctylus , 
Pleihodon, and Desmognathus. A spermatkeca also occurs in Spelerjpes , 
but no spermatozoa were found in it. Except in Pleihodon and Desmo- 
gnathus a ventral cloacal gland occurs in addition to the spermatkeca ; 
and in addition to the spennafhecal tubules other tubules occur on the 
dorsal side of the cloaca in Amblystoma , Spelerjoes, and Necturus. The 
secretion of the cloacal glands is employed at the time of ovulation. 
The three glands of the male, as recognised in Triton , the cloacal, 
abdominal, and pelvic, occur in the five genera examined. This suggests 
that spermatopkores are deposited by all of these, and it seems probable 
that the mode of mating and fertilisation is almost uniform in Urodela. 
Dorsal and ventral ciliated tracts occur in the males of the five genera 
examined. Cilia in the cloaca of the female were detected only in 
Amblystoma and Plethodon glutinosus , but the tract was not as extensive 
as in the male. 
Segmentation of Egg of Amphibia and Teleostei.§ — M. E. Bataillon 
has made a study of the relations which exist between the first groove of 
segmentation, and the embryonic axis in Amphibia and Teleostei. He 
concludes that in spherical eggs with a total segmentation, which have 
the first two grooves vertical and the third horizontal, the first plane of 
division passes through the plane of symmetry of the future embryo. In 
eggs with partial segmentation, which do not have the third groove per- 
pendicular to the first two, the first plane of division is perpendicular to 
the plane of symmetry of the future embryo. 
* Journ. Anat. Physiol., xxxi. (1895) pp. 511-95 (3 pis.). 
t Anat. Anzeig., xii. (1896) pp. 152-7. 
% Trans. Araer. Micr. Soc., xvii. (1896) pp. 261-301: (4 pis.). 
§ Comptes Rendus, cxxii. (1896) pp. 1508-11. 
