C. A. White—The Genus Pyrqulifera Meek. 277 
It will ever be a source of profound regret to the many 
friends of Dr. Henry Draper that he did not “live to complete 
the research to which the foregoing investigation was prelim- 
inary. With his new and admirably equipped laboratory, and 
with this powerful and thoroughly corrected photographie 
spectroscope at his command as one of its first fruits, no one 
can doubt that he would have secured with it results of the 
highest value to astronomical, and especially to solar, physics. 
ArT. XXXVI.—The Genus Pyrgulifera Meek, oe Se Associates 
and Congeners ; by CHARLES A. 
THE molluscan fauna of the Laramie Group of Western 
North America has a remarkable uniformity of character 
throughout its known geographical extent, from Mexico to 
British America, with the important exception of a region lyin 
in Utah and Southwestern Wyoming. The strata of this region 
are underlaid and overlaid respectively by the equivalents of 
the same formations which underlie and overlie other parts 
of the Laramie Group, ne such contacts are known. 
They are therefore referred to the Laramie Group although they 
hold a different molluscan fauna which, in my publications, I 
have usually designated as the Bear River Laramie, to distin- 
guish it from the fauna of the greater part of that extensive 
grou 
This Bear River Laramie fauna contains not only types of 
mollusea which are not found in that of the principal part of 
the regress Group, but which are not known among any other 
orth American fauna, either fossil or recent; and, what is 
still more eiaekatis a fauna which nearly approaches it, a 
regards the types referred to, is now living in Lake Tangune 
yika, Afriea. 
e mollusean fauna of this lake, whose waters are almost 
bitinels fresh, has been published by Messrs. S. P. Woodward,* 
Edgar A. Smith + and H. Crosse.t Some of the forms are 
n,and M: 
Tan, nganyika and the neigebockeod lof vii i, Ce ntral 
1880, pp. 344-352; pl. xxxi. On a oie ction of shee. from Lakes Fonebeiar 
and Pa ese and ole localities in Bast Africa. ‘oe. Zool. Soc. Lond., 1881, 
276-300, pl. xxxii-xxxiv. Description of two new Species of Shells from Lake 
Tasigenyiie Proc. bongo Soc. Lond., 1881, pp. 558-561; two w 
Faune malacologique du Lac yika. Journal de Conch., 
Crosse, H. Fau . ( : 
Paris; April, 1881, | aa 105-139, pl. iv. Supplement a la Faune malacologique de 
Lac Tanganyika. Same Journal, October, 1881, pp. 277-306. 
