

1891.] The Vermilion-Spotted Newt. 10gI 
tioned. Some were allowed to go on till hatched. This occurred 
in thirty-three days after the eggs were laid. 
After laying the eight eggs no more were laid for over a week. 
She was then placed -with a male for two or three days, when 
mating again occurred. After mating, she was again isolated as 
before to see if the ovulation would recommence, and if the eggs 
would be fertile. Seven days after isolation she commenced to 
lay eggs, and continued to do so until six or seven were laid. 
These proved fertile, and several stages of development obtained. 
This experiment indicates that for a single mating about six eggs 
may be internally fertilized, about the number found in the two 
Oviducts at one time. It indicates, further,that in nature more 
than one mating probably occurs (see below); and finally, almost 
certain proof is given that the eggs are not externally fertilized, 
as in the last experiment none were laid until seven days after 
isolation. Three other females were isolated as described above, 
and the eggs proved fertile. 
From these experiments it appears almost certain that the ova 
are internally fertilized, and as to the way in which the zoosperms 
reach the eggs, as there is no approach to a true copulation, the 
explanation of Professor Baird ('51) must be the correct one: 
“ The seminal matter becomes diffused in the water, and fecun- 
dates the ova while still in the lower part of the oviduct.” Or 
more probably the spermatophores recently described by Zeller 
(90) and Jordan (91) in some way aid the entrance of the zoo- 
sperms more surely than would simple diffusion in the water. 
The time of ovulation was found to begin the first week in 
April in specimens obtained from a spring-fed pond, and to con- 
tinue in different specimens from this pond till after the first of 
May. In specimens from Cayuga Lake, June 13th, eggs were 
obtained until June 18th. Probably in specimens obtained later 
eggs might have been obtained also. It would appear from this 
that the ovulating season is much earlier in the inland ponds than 
in the lake. 
Autumnal Mating.—lIf adult specimens are obtained from their 
natural habitat in the autumn, the males will be found to possess 
the dark horny toe-tips and the ridges on the thighs as shown in 

