1020 Review of Report C, 2d Geol. Surv. of Penna, (O i 
of this Anodonta extends over a vast area, embracing thousands 
of square miles of which as yet but little is known. 
Every item bearing upon the geographical distribution herein 
referred to, and more elaborately discussed in my recent paper 
indicates the mountain lakes as the sources from whence the spe 
cies have migrated, and point also to their descent from northerly 
regions as well as from higher altitudes, and also contribute addi- 
tional testimony as to the antiquity of these widely-spread though — 
inferior forms of animal life. A 
Admitting the presence of Physa humerosa within the drainage — 
of the Pecos, to which we find it accredited, and considering the 
new locality for Anodonta californiensis which Mr. James he o 
given us, and the fact that the Zwmerosa form of Physa seems to : 
be (geographically within the southerly portion of our West : 
American or occidental Anodon province) a pretty constant com — 
panion with said fresh-water mussel, we are encouraged to hope 
that we may find this aspect of the general West American fora 
of Anodon represented within such drainage areas as contain Of 
are inhabited by the Physa. = 
702 
AL 
REVIEW OF REPORT C, SECOND GEOLOGIC 
SURVEY OF PENNSYLVANIA. i 
BY DR. PERSIFOR FRAZER.” 
HIS new volume of the publications of the Pennsylvania 9” 
vey deserves much more than a passing notice, from the em 
nence of its editor and the number and nature of the cHHGS 
which it challenges. ; I 
As to the latter they should mence with the title page” 
certainly ! 
ally to the writer and in his pages (54 to 64) of this vo 
will be advisable to consider his part of the volume Ars d 
doing so the writer wishes to protest against the heading of pag” 
which should have been altered to conform to the title page 
1 On the History and Distribution of the Fresh-water Mussels, da 
Cal. Acad., Nov. 20, 1882. d £ 
2C, Second Geological Survey of Pennsylvania. “ The Geology ® a. 
County after the Surveys of H. D. Rogers, Persifor Frazer and Charles 
Edited by J. P. Lesley. Harrisburg, 1883.” ce 
