228 MR. F. H. WELCH ON LEPUS AMERICANUS. [Apr. &, 
Society’s ‘ Proceedings’ for the same year (page 557). In that paper 
I described a new Frog, which I proposed to name Pachybatrachus 
robustus. I now find that, by a singular coincidence, the very same 
generic term was applied about the same time by Professor W. 
Keferstein, M.D., of Géttingen, to another new Batrachian. This 
appears in the third number of the ‘Archiv fiir Naturgeschichte’ 
for 1868, where, at page 273, Professor Keferstein has published a 
description of his Pachybatrachus. 1 therefore beg leave to with- 
draw the name which I before gave, and to substitute for it the 
more appropriate term Clinotarsus. I propose therefore that my 
new Frog should bear the name CLINOTARSUS ROBUSTUS. 
2. Observations on Lepus americanus, especially with refer- 
ence to the Modifications in the Fur consequent on the 
rotation of the Seasons, and the Change of Colour on 
the advent of Winter; based on Specimens obtained in 
the province of New Brunswick, North America. By 
Francis H. Wetcu, Assistant-Surgeon, Ist Battalion, 
22nd Regiment*. 
This species is the sole representative of the Leporide in the pro- 
vince of New Brunswick. In the List of Mammalia of the Portland 
Natural-History Society it is called the ‘‘ White Hare,” and in the 
‘New York Fauna,’ by De Kay, the “Northern Hare.” It is also 
termed the ‘‘American Varying Hare,” and was for a long time con- 
founded with the L. variabilis of Europe. Its geographical range 
appears as yet undetermined. According to Sir John Richardson it 
‘is found as far north as 64° 30', Fort Enterprise, forming the staple 
food and clothing of the Hare Indians on the banks of the Mackenzie 
River.” Its southerly limits are given by De Kay as “‘ the northern 
parts of Pennsylvania and the mountain-tops of the northern part 
of Virginia.” Of the many species of Leporide inhabiting the North- 
American continent, it appears to be the only one that undergoes a 
complete change of colour during the winter+,—the Greenland Hare 
remaining white during the whole year, L. nanus becoming of a 
lighter hue, and occasionally iron grey, during the winter months, 
and L. glacialis assuming occasionally in the adult a greyish tint 
during the summer, limited to the points of the hair, the deeper 
parts remaining white permanently, the young, however, being born 
grey, and changing to white on the advent of wintert. Its weight 
varies—in its southernmost limits reaching 63 lbs. ; in New Bruns- 
wick averaging 3 lbs. ; in Hudson’s Bay Territory 4 lbs. 
* Communicated by Mr. G. Busk, F.R.S. 
t i. e. provided the L. campestris be only a variety of L. americanus, as stated 
by Sir J. Richardson, but denied by Baird. 
+ Fauna Boreali-Americana. 
