
A STRUCTURAL FEATURE CONNECTED WITH 
THE MATING OF DIEMYCTYLUS 
VIRIDESCENS. 
WILLIAM A. HILTON. 
THERE seems to be very little doubt at present that the 
fertilization of Urodela is internal. Since Spallanzi in 1785 
proved internal fertilization must take place with Triton, many 
investigators have shown conclusively that such is the case in 
other species. 
The mating habits of a number of salamanders have been 
observed, but very much is yet to be learned about many forms 
concerning which we now know little more than the mere fact 
that fertilization is internal; however, it seems very probable 
that in all Urodela fertilization is accomplished by a similar 
method. In most cases the courtship is more or less compli- 
cated and terminates with the female following the male, who 
emits a spermatophore containing zoósperms, which is received 
by the cloaca of the female as she passes over it. 
There are many variations in the mating habits of different 
forms described, but unfortunately few species are easy to 
observe. Of American forms practically nothing is known 
of the more terrestrial species. Diemyctylus viridescens 
and D. torosus of the aquatic species are about the only 
ones in which a satisfactory idea of the mating has been 
obtained. 
A number of observations have been made upon European 
salamanders by Robin (74), Gasco (80), and Zeller (90), who 
have given good accounts of their habits. With Triton, for 
instance, Zeller has carefully described the antics of the male 
before the female ; these may extend over a period of hours; 
he rubs against her and rushes before her. At length she is 
attracted by him, and as he moves off she follows and receives 
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