262 MR. NEWPORT ON THE IMPREGNATION OF THE OVUM IN THE AMPHIBIA 
having passed, and the function being fulfilled. Thus too, I have noticed that, when 
from accident, but more especially when from reduction of the temperature in the 
surrounding medium, the season of spawning has been greatly retarded, the impreg- 
nating power of the male is much diminished, and perhaps is almost exhausted, 
through constant shedding of the spermatic fluid, which, I have found, often takes 
place when the oviposition of the female is delayed, and the individuals are disturbed 
or interfered with. The female is then forsaken by her partner, and when this occurs 
it rarely happens that the connubial intercourse of these two individuals is recom- 
menced When this separation has taken place, there is usually but a small quantity 
of fluid remaining in the male organs, and even in that, the number of spernmtozoa 
is considerably diminished, and their power of motion is exeeedmgly feeble ■, while the 
quantity of molecules and cells is increased. When several days, or a week or two 
have elapsed, there are not only fewer spermatozoa, but those which remain are 
much more feeble in action. This is exactly what occurs also in the Toad. t^e 
sixth of June I found that the testes and efferential ducts in a male Toad, which had 
been kept from pairing during the whole season, were still filled with spermatozoa, 
together with a very small quantity of liquor seminis with active molecules mo^ung 
in it ; but that, though the spermatozoa were in full abundance, nearly t e w o e o 
them'were entirely motionless, while the motions of the few which still gave evidences 
of vitality, were exceedingly feeble, whether the spermatozoa were examined simply 
in the fluid portion of the semen, or whether they were mixed with water, m which, 
as is well known, the motions are always at first greatly increased. ^ \ • 
A similar reduction in the number of the spermatozoa and diminution of their 
motive power, appears to exist in animals which have become exhausted through long 
confinement or want of food; at least, if we may so judge, from a few obserN^tions 
on the Tritons. A Triton palustris, which had been captured on the seventh ot iMay, 
and accidentally confined without food till the sixth of June, was examined immediately 
after death. The eflerential ducts were well-filled with spermatozoa contained m a 
distinctly perceptible quantity of liquor seminis. When the spermatozoa were ex- 
amined, without the addition of water, their motions were regular, but apparendy 
very much slower than usual, being uniform and undulating, without that peculiar 
rapid ciliary action of the spirally twisted tail, which is so constantly referred to as 
characteristic of the spermatozoa of the Tritons and of some other Amphibia. W hen 
water was added, the motions were immediately accelerated, and the tail, whic i 
before was merely flexed, and almost longitudinally extended from the body, becanie 
folded and entwined around it, and its rapid ciliary movements were commenced 
But these gradually subsided within a very few minutes. In another specimen, whic 
had been captured at the same time as the preceding, and confined undei simi ai 
circumstances, but which, at the time of examination, had been already dead tm* 
more than twenty-four hours, scarcely any spermatozoa remained in the testes, or m 
the efferential ducts. There was a great quantity of cells, with granular nuclei, in 
