No. 387.] DESMOGNATHUS FUSCA. 241 
specimen, although still in the egg, and leaving a large yolk- 
sac, was in other respects a fully developed larva. The pig- 
mentation was complete, the external gills fully developed, and 
the feet had the full number of distinct toes (4 anteriorly, 5 
posteriorly). , 
Larve of Desmognathus fusca.— From the suggestions of 
the previous paragraph, if becomes probable that the larva 
of Desmognathus remains in the egg until very well developed. 
My oldest embryo, taken from the egg June 30, is 13 mm. in 
length, still possessing so large a yolk-mass that it was evidently 
intended to remain in the egg for a much longer time. 
I have taken Desmognathus larve only during the months of 
August—October, and these vary from 20-30 mm. in length, 
with external gills much reduced. 
During fall and early winter the smallest adults are found 
35-40 mm. in length, and differing from the largest larvæ 
mainly in the absence of the external gills. 
Summing up the evidence, it becomes probable that the 
larvee of Desmognathus remain in the egg until nearly adult, 
that they emerge from the egg in midsummer, that the gills, 
smaller at the time of hatching than at an earlier embryonic 
period, become gradually lost —a process which becomes com- 
plete during the late fall of the same year in which the eggs 
are laid. This history will readily explain the fact why the 
larval Desmognathus, perhaps the commoner of the two species 
considered, is so rarely met with. I have collected many hun- 
dreds of the larvæ of S. bilineatus, and a very few, not more 
than twenty in all, of the larve of D. fusca. In habits these 
larvee resemble the adults. They avoid the deeper pools which 
abound in the larve of the other species, and lie where it is 
very shallow or in the wet sand, where they may find in places 
just water enough to cover them. When alarmed they run 
rather than swim, often abandoning the water, running with a 
series of quick jumps over the wet sand. Copr’s only mention 
of this larva is so short and couched in such general words as 
to be applicable to either species. He says: “Its delicate larva 
may be observed darting rapidly from place to place, seeking 
concealment among mud and leaves.” The color and marking 
