F. GEOGRAPHY. 211 



special charge of the inollusks, and his time was chiefly em- 

 ployed in the drawing of perishable specimens. As an ac- 

 curate summary of the zoological collection can not be given, 

 a slight sketch of the general scheme alluded to above is ap- 

 pended, that its significance as a whole may be understood. 



In the first place, the endeavor was made to collect as 

 many specimens of the same species as possible, in every 

 stage of growth and every condition of development, in order 

 to ascertain the range of variation in each species. The sec- 

 ond object was to learn the boundaries of the different faunae, 

 especially along the Pacific coast, from the Straits of Magel- 

 lan to California. In this was included, wherever it was 

 possible, the fishes from the rivers on the western slope of the 

 continent for comparison with those of the eastern ; this part 

 of the plan, however, it was difficult to execute, because Pro- 

 fessor Agassiz had not the means of collecting in his own 

 hands. During the whole journey care was taken to have 

 made large numbers of anatomical preparations of such parts 

 of marine animals as can rarely be well studied from alco- 

 holic specimens. The most valuable of these preparations 

 were those offish-brains. 



It is hardly necessary to add that the great opportunity 

 for scientific investigation afforded by the voyage of the 

 Hassler is due to the liberal policy of the Superintendent of 

 the Coast Survey, who is ever ready to combine the larger 

 interests of science with the special work of the survey, where 

 it can be done without detriment to the latter. It is proper 

 to state, however, that the means for making the zoological 

 collection were contributed by gentlemen of Boston, who 

 raised nearly $20,000 for the purchase of alcohol, jars, and 

 other apparatus for collecting on a large scale, and for 

 charges of freight in forwarding the specimens from foreign 

 ports. The latter charges, however, were comparatively 

 small, owing to the liberality of both railroad and steam-ship 

 companies, of the commanders of our naval forces in various 

 ports, and of the captains of vessels employed upon whaling 

 voyages or in private mercantile enterprises. 



EXPLORATION IX CENTRAL AMERICA. 



General Banks has introduced into the House of Repre- 

 sentatives a resolution instructing the Secretaiy of the Navy 



