158 General Notes. [February, 
nian and Turonian divisions of Europe. The third sub-flora is 
that of the Belly river at the base of the Fort Pierre group. 
Though separated from the Laramie by the Pierre and Fox hill 
groups, it introduces the Laramie or Dominion flora, which con- 
tinues to the top of the Cretaceous, and probably into the Eocene, 
and includes several species still surviving in America. Next 
comes the Laramie group itself, the fossils of which are found in 
Canada, chiefly in the lower and upper beds, the middle beds 
being poor in plants. Sir W. Dawson concludes that no cause 
for the mild temperature of the Cretaceous other than change of 
elevation need be invoked. 
Tertiary —According to Woodward, fifteen species of fossil 
sirenians have been referred to Halitherium, while two consider- 
ably larger species, both found in Italy, are placed in Felsinothe- 
rium, and closely resemble Halicore in dentition. Prorastomus 
isit c.i4 p.m. m.33=48. Felsinotherium has i }} m. 33. 
An interesting discovery was a cast of the interior of the skull of 
Eotherium egyptiacum at Mokattam, near Cairo, in 1875. The 
brain of the huge Rhytina is only one-sixth of the size of that of 
the manatee or dugong. The total number of extinct sirenians 
enumerated by Woodward, including Chirotherium from Pied- 
mont; Chronozoon from New South Wales; Crassitherium from 
Belgium’; Dioplotherium and Hemicaulodon from South Carolina 
and New Jersey; Pachyacanthus from near Vienna; Rhytiodus 
and Trachytherium from France, and two extinct Manati, is 
twenty-eight. The recent species are three of Manatus and three 
of Halicore. Dr. Murie believes that the large number of fossil 
species described will probably have to be reduced into two or 
three genera. 
MINERALOGY AND PETROGRAPHY.! 
d 
proving that the shapes of etched figures were independent of the 
1 Edited by W. S. BAYLEY, Johns Hopkins University, Baltimore, Md. 
2 Quart. Jour. Sci., 1, 1816, p. 24. 
3 Sitz.-Ber. der Akad., Wien, 1855, 15, p. 59. 
* Poggendort’s Annalen, 124, p. 329, etc. 
