THE HISTORY OF ZOOLOGY 511 



tions, the most successful perhaps being some of the French 

 and Scandinavian investigations, the voyage of the British vess 

 the Challenger, 1872-1875, and the three cruises of the Blake 

 under the direction of the United States Fish Commission, in 

 1 877-1 880, with Alexander Agassiz as naturalist. 



To-day biological investigations are being actively carried on 

 in almost every highly civilized country; the centers of this 

 activity are the universities and the zoological and agricultural 

 stations. In almost every university and college are found 

 well-equipped laboratories for zoological research. Most in- 

 vestigators are students or teachers in such institutions ; the 

 number of naturalists who devote their time to investigations 

 without teaching is small. Of the various experiment stations 

 the marine are naturally the most extensive contributors to zoo- 

 logical knowledge; of these the most celebrated is the well- 

 equipped station at Naples, founded in 1870 by the German 

 naturalist Dohrn. It is provided with an excellent working 

 library and an unsurpassed aquarium, while its publications arc 

 among the finest in the world ; scientists of all nationalities 

 repair there for research, and the United States is always well 

 represented. Almost every European country with a seacoast 

 has one or more zoological stations, and many are scattered 

 along the coasts of the United States. Other aids to the study 

 of biology are found in the numerous scientific libraries which 

 have been established within recent years ; the valuable collec- 

 tions, such as those of the British Museum in London, the 

 Imperial Museum in Vienna, the American Museum in New 

 York, and the Agassiz Museum in Cambridge; the establish- 

 ment of aquaria, as at Naples, Berlin, Amsterdam, and New 

 York ; and also the maintenance of zoological gardens, such as 

 are scattered over Europe and the United States. 



