1020 General Notes. 
Amphicyon, Dinocyon, Cephalogale, Simocyon, Oligobunis, and 
probably Enhydrocyon. In the Canide, Dr. Schlosser appears to 
us to admit too many genera; at least we cannot clearly make out 
generic differences from his deseriptions. On the other hand the 
genera of Mustelide, though numerous, are sharply defined. We 
note a couple of errors in the matter of American species. Canis 
brachypus Cope is not an Eocene, but an upper Miocene species 
(Ticholeptus beds). Aelurodon ferox and Canis saevus cannot be 
well referred to different families, as they were established on the 
superior and inferior molars of the same species. Four plates 
accompany this memoir.—£E. D. Cope. 
MINERALOGY AND PETROGRAPHY.' 
PETROGRAPHICAL News.—There have recently appeared two 
interesting papers upon the Cortlandt series of eruptive rocks, and 
the changes they produce in the surrounding mica-schists and lime- 
stones. The first paper is by Mr. J. EF. Kemp, who reports the 
results of his examinations of an extension of the series west 0 
Stony Point, N. Y. He finds the eruptives to be of the same 
general character as those described by Dr. Williams,’ from near 
_ Peekskill. In one of these he notices the alteration of brown 
hornblende into green augite. He further finds that limestone 
upon the contact with these eruptives has undergone an alteration, 
during the course of which tremolite has been developed. Dr. 
Williams’s‘ paper deals with the contact phenomena observed in 
the rocks surrounding the eruptives in the Stony Point region. 
The unaltered mica-schists consist of quartz, biotite, muscovite, 4 
little feldspar, tourmaline, and occasionally zircon. Upon approach- 
ing the eruptives they lose their foliati d havedeveloped in them: 
garnet, sillimanite, staurolite, scapolite, cyanite, margarite, ripidolite 
and corundum. The sillimanite is found in radiating bundles of fibres. 
The ripidolite (or clinoclor) js derived from the biotite of the schists. 
The margarite has the macroscopic appearance of muscovite. Tn 
the thin section, it is distinguished from this mineral by its high 
refractive index, its extinction of 6°-10°, its numerous twins par- 
allel to oP, and its large optical angle (114° in air). Its compo 
sition is: — 
' Edited by Dr. W. S. Bayley, Colby University, Waterville, Me. 
2 Amer. Jour. Sci., A , p. 247. 
; Cf. Amer. Naturalist, 1886, p. 275 ; 1887, p. 569. 
Amer. Jour. Sci., Oct., 1888, p. 254. 
