10 Mr J. D. Dana on the Volcanoes of the Moon. 



rieri) ; some Bhinoceros, not yet well determined ; many An- 

 thracothcrium ; and the genus Cainothermm^ Bravard, (Oplo- 

 theriuniy Delaiz.), which connects the Anoplotherium with the 

 Ruminants. 



The Ruminants present many species of Atnphitragulus, a 

 new genus of the family Moschus, and which, in its dentition, 

 has relations on the one hand with the Llamas, and, on the 

 other, with the Anoplotherium. Some bones not well known 

 and described under the name of Dremotherium, are likewise 

 referred to in the order of ruminants. 



The Birds have not yet been determined. The bones of 

 of palmipedes, waders, and birds of prey, have been found. 



Among the Reptiles, M. Pomel mentions a land tortoise 

 (Testudo giganted), two emydes, an emysaurus {E. Meilheu- 

 ratiai), a trionyx, a crocodile {C. Batelii), a Dracoenosaurus, 

 an animal nearly related to the dragon in its dentition, and 

 one or two frogs. 



Fishes likewise exist, but the fragments have as yet been 

 imperfectly studied. — Professor Flctety Bib, Univer. de Geneve ^ 

 15th September 1846. 



On the Volcanoes of the Moon. By JAMES D. Dana. Ex- 

 tracted from the American Journal of Science, vol. ii., 

 Second Series.* 



The surface of the moon affords a most interesting subject 

 for the study of the geologist. Though at a distance of 

 many thousand miles, the telescope exhibits to us its struc- 

 ture with wonderful distinctness ; and already, as a learned 

 astronomer has observed, we are better acquainted with the 

 actual heights of its mountains, than with those of our own 

 planet.t Having an atmosphere of extreme rarityj (if any) 



* Read before the Association of American Geologists and Naturalists, Sept. 

 1846. 



t M. xVrago, Annuaire des Longitudes, pour I'an 1842, 2d ed., Paris, 1842. — 

 P. 526, in an article on the Lunar Volcanoes, Arago says : — " II est remarquable 

 que grace au zele et a I'exactitude d'llevelius on ait connu la hauteur des mon- 

 tagnes de la Lune beaucoup plus tot que la hauteur des inontagues de la Terre." 



X The evidence in favour of the existence of au atmosphere and of water in 

 the moon, liithcrto obtained, has not been deemed satisfactoi7. Ilerschcl, at an 



