F. GEOGRAPHY. 141 



the fauna and physical condition of the deeper waters ; and 

 we find in the last number- of Silliman's Journal a more de- 

 tailed account of that portion of the work carried on in Lake 

 Superior, upon the United States steamer Search, under the 

 direction of General Comstock, of the Lake Survey, as report- 

 ed by Mr. Sidney J. Smith, the zoologist of the expedition. 



The deepest water met with was 169 fathoms, the bottom 

 being there covered, as in all the deeper portions of the lake, 

 with a uniform deposit of clay or clay mud ; and not the 

 slightest trace of saline matter was detected in the water in 

 any part of the lake. The temperature, every where below 

 thirty or forty fathoms, varied very little from 39 Fahr., al- 

 though, in August, it varied at the surface from 50 to 55. 

 The fauna at the bottom was found to correspond to these 

 physical conditions. In the shallow waters the species vary 

 down to thirty or forty fathoms, after which the deep-water 

 fauna begins, and the species appear to be uniformly distrib- 

 uted. The list of species is meagre, and the deep-water re- 

 gion is characterized rather by the absence of many of the 

 shore species than by the presence of any peculiar class. The 

 same crustaceans and marine forms met with in 1870 in Lake 

 Michigan were also found here abundantly, together with the 

 same species of Pisidium; and some of the crustaceans have 

 so far been undistinguishable from those found in Lake Wet- 

 ter, in Sweden. The detailed account, of which that in the 

 Journal of Science is an abstract, appears in the report of the 

 chief engineer of the army to the Secretary of War, just pre- 

 sented to Congress. 4 D, November, 1871, 373. 



EXPLOKATIOXS IX THE WEST INDIES. 



In the search for new regions of exploration and discov- 

 ery, it is not a little surprising to be assured that, taking the 

 West Indies as a group, we know almost as little of their 

 natural history as we do of that of Central Africa, especially' 

 of the islands east and south of the Greater Antilles. Thanks 

 to the labors of Dr. Gundlach and Professor Poey in Cuba, of 

 Dr. Bryant in the Bahamas, of Mr. March and Mr. Gosse in 

 Jamaica, of Mr. A. E. Younglove in Hayti, of Dr. Bryant, Mr. 

 Swift, and Mr. Latimer in Porto Rico, of Mr. Swift in St. Thom- 

 as, of Mr. Galody in Antigua, of Mr. Julien in Sombrero, and 

 of Mr. Newton in Santa Cruz, we have a fair knowledge of 



