395 
dorsal cord is seen between the auditory capsules only. If the 
dorsal cord is to be regarded as an index of the extent of the 
parts considered serially homologous with vertebrz, then it may 
be inferred that the vertebral column extends originally through 
the base of the cranium, and consequently that the cranium 
conforms to the vertebral type. 
Dr. Wyman also gave some account of the habits of 
the Alewive in depositing its eggs, as observed in Fresh 
Pond, in Cambridge. 
The eggs are about 4, of an inch in diameter, and are laid 
in April and June in the greatest abundance; the localities 
selected being usually gravel or sandy bottoms, but sometimes 
they are laid among small stones, and in five or six inches of 
water. The alewives move ordinarily in small shoals along the 
borders of the pond, but varying from two or three to very 
numerous pairs. The males follow the females very closely, and 
when entering a small shallow cove, often some of the number 
are pressed entirely out of the water on the shore. 
The Corresponding Secretary announced the receipt Eo» 
of the following letters, viz: — ide 
From the Royal Society of. London, March 8, 1856, acknowl- — 
edging the receipt of the Society's publications; das Bibliothe- 
kariat der K. Bayerischen Akademie der Wissenschaften, January 
12,1856, acknowledging the same, and presenting various works ; 
from the same, January 20, 1856, asking for duplicate copies of 
all works presented by the Society, and offering to reciprocate 
With its own publications ; die K. Akademie der Wissenschaften, 
Wien, November 1, and December 30, 1855, presenting its pub- 
lications; der Zoölogisch-botanischer Verein, Wien, December 
12, 1855, presenting Vols. 3 and 4, and parts 1, 2, and 3 of 
Vol. 5 of its Transactions, and inquiring as to the reception o 
Vols. 1 and 2; George Frauenfeld, Wien, December 12, 1855, 
Presenting publications of his own and asking an exchange on 
ae part of the Society. 
S Dr. Brewer announced the second arrival of specimens, : 
~ Principally of Birds, Plants, and Eggs, from California, - 
