PROGRESS IN BIOLOGICAL INQUIRIES, 1922. 13 



During the year arrangements have been made with the National 

 Museum and with a number of specialists to identify the various 

 forms caught in the beam trawl, bottom net, dredge, and surface nets. 

 This material is being separated, and a considerable quantity has 

 been shipped to specialists. 



The purpose or this investigation is, first, to determine the normal 

 biological and physical conditions throughout the year, so that when 

 great mortality of fishes, oysters, clams, crabs, etc., occurs there will 

 be normal data at hand from which to determine the abnormal con- 

 ditions that bring about the trouble ; second, to learn all that is pos- 

 sible concerning the movements of layers of water of different 

 density, different temperature, and different plankton content (fish- 

 food value), in the hope that the information may throw light on the 

 migration of fishes and crabs into and in Chesapeake Bay at certain 

 times of the year; third, to study especially the fauna of deep holes, 

 which occur in many places; fourth, to study" the so-called "barren 

 bottoms " at the mouths of rivers ; and fifth, to gather as much infor- 

 mation as possible that will bear on the conservation of the fisheries 

 resources of Chesapeake Bay. 



LONG ISLAND SOUND. 



In connection with the extremely difficult investigations of the 

 problem of the failure of oyster set in the waters of Long Island 

 Sound and its shores, the bureau has been in considerable measure 

 baffled for want of the fundamental information relative to the dis- 

 tribution and variations of temperatures, salinities, and currents, 

 as well as for lack of definite information regarding the extent and 

 degree of pollutions detrimental to oyster culture and to the fisheries. 

 It has therefore been necessary to inaugurate a hydrographic and 

 biological survey of Long Island Sound having immediate regard 

 to the practical problems confronting the bureau in attempting to 

 serve the oyster industry and other fisheries. This investigation is 

 being conducted by P. S. Galtsoff, recently appointed naturalist of 

 the Albatross. Provisional plans for the work were formed in 

 May, 1922, but circumstances made it necessary to delay the actual 

 beginning of field observations until the beginning of the ensuing 

 fiscal year. Since the Albatross has been indefinitely laid up for 

 lack of the funds necessary to keep her in service, the fisheries 

 steamer Fish Hawk., which is well suited to the purpose, will be 

 employed in tlie conduct of the investigation in the field. 



UPPER MISSISSIPPI RIVER. 



An investigation of free-floating organisms (plankton) in the 

 upper Mississippi Eiver was carried out by Paul S. Galtsoff, then 

 temporary investigator for the bureau and now naturalist of the 

 Albatross. The object was primarily to obtain quantitative data 

 regarding the fundamental food supply of fishes in the river and 

 to throw light upon the effect of natural and artificial impounding 

 of large rivers upon the production of food for fishes. Special 

 attention was given to Lake Pepin, a lake formed by natural causes 

 in the course of the Mississippi, and to Lake Keokuk, which is 

 approximately the same size as the former lake and which has been 



