56 
KENDALL: NEW ENGLAND CHARES. 
The Silveb Trout of Monadnock Lake. 
Salvelinus agassizii (Garman). 
Plate 6, Fig. 9 (male); Fig. 10 (female). 
Attention seems first to have been attracted to the habits of this trout, in that they 
differed so radically in some respects from those of the Common Trout (S. fontinalis), which 
this fish was once thought to be. 
An early article entitled “Observations on some of the habits of Salmo Fontinalis” by 
Samuel L. Bigelow, M. D., (Boston Journ. Nat. Hist., vol. 6, p. 49, 1850) follows verbatim. 
Dr. Bigelow does not definitely name Monadnock Lake but the description and location suffi- 
ciently indicate it. The habits of the fish also, as described, agree exactly with the known 
habits of the Monadnock-Lake Trout. 
Dr. Bigelow said: “The following observations on the habits and peculiarities of a species 
of Salmo, were made in a comparatively short space of time, without any reference to science 
but merely as a source of pleasure to myself, and to gratify a natural curiosity. 
“The pond in which these trout are found, is situated at the base of the north-east ridge of 
the Monadnock mountain. It covers an area I should think, of seventy-five or one hundred 
acres, and is so deep about the centre, that soundings have not been found, though a line has 
been sunk two hundred feet. It is supplied entirely by springs at the bottom, which is com- 
posed of red and white sand and rocks, so far as the depth of the water will permit of an examina- 
tion. The water is always very cold, and so clear that the bottom may be seen, in a bright 
day, to the depth of twenty-five or thirty feet; and although there are neither inlets nor out- 
lets, its height is nearly the same at all seasons. Its depth increases from the shore, where it 
is only a few inches, in some parts gradually, and in others rather abruptly. The form of the 
pond is quite irregular, and has been fancied by some to correspond very exactly to that of the 
base of the mountain, which is close beside it. From this circumstance, together with its 
great central depth, has arisen a legend of its having been once filled by this mass, now a moun- 
tain, which was heaved out by some convulsion of nature. 
“The south-west shore is more stony, and less exposed than almost any other, and here 
it is that the trout form their beds and come up to spawn. Another natural advantage which 
this point possesses over others is, that here the change from shallow to deep water is quite 
abrupt, affording the trout a better chance for escape in case of fright or danger. 
“ Their beds, as they are called, are merely small cavities formed by the accidental posi- 
tion of three or four stones, sunk to their upper surface in sand. Their capacity is generally 
from a pint to a quart, and their forms are various; sometimes conical, with the base upward 
