REPORT OF COMMISSIONER OF FISH AND FISHERIES. CXXI 



Mexico on its way south to Mount Orizaba, which was the objective 

 point. According to Mr. Woolman : 



In mouutainous regions the number of species of fislies is small, and this is espe- 

 cially true in Mexico, where the streams are short, their basins isolated, and tlieir 

 volume of water varies greatlj^ from one season to another. 



The total number of species obtained was only 24, of which G were 

 new to science, and as the entire collection was made in the head 

 waters of the streams, all of the forms belong strictly to fresh water. 

 Of the species collected south of the Rio Grande, 50 per cent belonged 

 to the GypripJdce and 30 per cent to the GyprmodontidcE, the remaining 

 20 per cent representing five other families. The streams visited are as 

 follows: The Rio Grande at El Paso del Norte; Rio de los Couchas at 

 Chihuahua; Rio de Lermaat Salamanca; the lakes and canals about the 

 City of Mexico, and the Rio Blanco at Orizaba. Some of the collections 

 were made at altitudes of 4,000 to 6,000 feet above the level of the sea. 



MISCELLANEOUS INQUIRIES. 

 FRENCH METHODS OF OYSTER-CULTURE. 



The marked depletion of oyster-grounds which has taken place on 

 some parts of the Atlantic seacoast of the United States, the diffi- 

 culty generally encountered in procuring an adequate supply of seed 

 for i^lauting purposes, and the very commendable efforts made or con- 

 templated with respect to the establishment of new oyster-producing 

 areas on both sides of the American continent, have all been fruitful 

 sources of inquiry, calling for information of a thoroughly practical 

 kind. To assist in meeting this demand the U. S. Fish Commission has 

 not only carried on many investigations and experiments relative to the 

 oyster question, but it has also sought to disseminate the experiences 

 acquired in other countries by printing, from time to time, accounts of 

 the methods employed by foreign culturists. 



The relative scarcity of oysters in Europe as compared with this 

 country and the high prices there received for them has led to a system 

 of cultivation which at present would be neither expedient nor i)rofltable 

 on our own coasts, and it is sincerely to be hoped that the time is still 

 far distant when this mollusk shall become a luxury to the American 

 people. But, however that may be, much benefit can undoubtedly be 

 derived from a study of the different systems resorted to in Europe, 

 some features of which may prove applicable to our own needs or be 

 at least suggestive. The French Exposition of 1878 was made the 

 occasion for bringing together the literature relative to the history and 

 conditions of oyster-culture in the several European countries where it 

 was then practiced or where experiments had been undertaken regard- 

 ing it. A comprehensive review of the subject, based upon inquiries 

 made at the same time, was also promised but never completed, and 

 translations only of some of the principal papers were published in tke 

 Fish Commission annual report for 1880. 



