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eae PROCEEDINGS OF THE NATIONAL MUSEUM. 387 
of June, contains seven eggs, four of which are in the left oviduct. 
Usually the larger number of eggs in snakes is found in the right oviduct. 
The eggs of this specimen are about the size of the yolk of a hen’s egg. 
In each is an embryo not larger than a common pea. 
The breeding habits of Crotalus do not appear to be well known. 
Prof. Putnam * dissected a female which he says contained in the ovi- 
ducts eight fully formed eggs, besides a number of smaller ones, which 
he supposed belonged to a later brood. It is more probable that all 
the eggs were really in the ovaries. A female rattlesnake, 39 inches 
long (U. S. Nat. Mus., No. 17959), was brought to me from western 
Pennsylvania by Mr. Hall. In this I find nine eggs, four of which are 
in the left oviduct. The eggs will average nearly an inch and a half in 
long, and an inch in short, diameter. In one of them I find an embryo 
about 3 inches long. The egg-coverings are extremely thin. The mother 
snake was captured some time in August, probably before the 15th. 
At what time of year the sexes unite I find nothing on record. Prof. 
8. W. Williston, who has had abundant opportunities for making obser- 
vations on C. conflwentus, states that the sexes pair in May. Nor do I 
know how large the young are at the time of their birth. M. Palisot 
Beauyois, as quoted by Dr. Goode, t says that he saw five young run 
into the mouth of a mother snake, and that these young were about 
the size of a goose quill. The young are undoubtedly much larger 
than this statement makes them. There is apparently as strong a ten- 
dency in observers to minify the size of the young of snakes as there is 
to magnify the size of the adults. 
I have been enabled to make some observations on Crotalophorus 
catenatus Raf. (Crotalus tergeminus Say.). In the American Naturalist 
for March, 1887, pp. 211-218, I published some notes on the breeding 
habits and young of this species. About September 1 two females, 
which had been kept in confinement, brought forth young, one six, the 
other seven. The young were not seen by myself at the time of birth, 
but on the Ist of January they were at least 10 inches long. From a 
female sent me from Paris, Ill., [ have taken an almost fully developed 
embryo (U.S. Nat. Mus., No. 17947). It measures 74 inches in length, 
and this is probably nearly the length which it would have been when 
born. A considerable amountof the yolk wasstill spread over and among 
the coils of the little snake; but, when its body was opened, a large mass 
of the yolk was seen to have been received within its walls. This would 
be sufficient to maintain life and growth until the little reptile could pro- 
vide for its own necessities. The fang is developed, and the egg-tooth is 
present, although it does not seem to be directed so much forward as in 
other species. In the oviduct, lying alongside of the embryo just de- 
seribed, was another egg which contained an embryo only about four 
inches in length. It was so deeply immersed in the yolk that its pres- 
*Amer Nat., Vol. 1., p. 133. 
tAmer, Nat., Vol. x11, p. 207. Proc. A. A. A. 8., 1873, p. 183. 
