1534 North American Batrachology in the years 1880-83. [Februaty, 
limbs commence to bud. At the age of sixty days all the external 
parts are formed, and it undergoes no external change except 
growth until the branchiz are resorbed, a process which occupies 
from three to five days. The entire series of changes, in vigorols 
examples, occupies about a hundred days. 
The same writer gives an account of the development of the 
Wolffian body in this salamander. It arises from the outer layer 
ofthe mesoderm asa solid rod of cells, and is at first largest 
anteriorly, a dorsal and ventral duct are then formed by the split- 
ting of the cells, and an opening into the body cavity is madè 
from the dorsal duct. The method of development of this orga 
differs from that observed in allied forms that have been wor 
out, and is most like that of the Elasmobranchiates. 
The same laboratory furnishes some interesting notes upon the 
secretion of the pepsin-forming glands of the frog, by H. F. Sewa! 
The œsophageal glands, which, when the intestinal- canal is empl; 
are full of fine granules, undergo marked changes in digestion 
losing the greater part of these granules during the process. These 
changes are started by the mere absorption of matter from the | 
alimentary canal, but the regeneration of the glands depends up?" 
the presence of new matter in the blood itself. eS 
The fifth Bulletin of the Illinois State Laboratory of Nate 
History is a list of the Batrachia and Reptilia found east of a 
Mississippi, by N. S. Davis and F. L. Rice. Siren lac 
credited to Northeastern Illinois. The Bulletin No. "i 
U. S. National Museum consists of a check-list of the Reptilia% 
Batrachia of North America. The classification is based 0n 
of Professor Cope, as set forth in Bulletin No. 1, of the st 
series. 
The work of Dr. J. J. Mason, upon the minute structure 
central nervous system of certain reptiles and batrachians ge 
uable addition to our knowledge of brain-structure in the pr 
illustrated as it is by artotype plates taken from negatives ' a | 
by the author. Numerous sections of the spinal cord and 
of Rana, Menopoma, Diemyctylus and Siren are ae gest 
transversely-developed spinal cord of Menopoma, deeply gsuttd 
posteriorly, contrasts greatly with the oval and slightly iagti? 
form of that of Rana. The writer does not claim to distil y 
between motor and sensory cells, and considers that the atl 
which makes the nuclei the true function centres of the neft ~ 
is an unproved one. 
of the 
a 
