36 1^' S. BUREAU OF FISHERIES 



The impounding of waters for various industrial purposes and the 

 consequent formation of artificial lakes bring about unusual condi- 

 tions that require special consideration if mosquito production is to 

 be prevented. Several such lakes in Southern States have been 

 examined for the purpose of securing information concerning the 

 effectiveness of Gambusia for mosquito control under the various 

 conditions found in these impounded waters. Conferences were held 

 with p'ublic-health officials and recommendations made for the plant- 

 ing and propagation of Gambusia. 



OCEANOGRAPHIC WORK 



The oceanographic work conducted by the division during the past 

 fiscal year has practically been confined to completing investigations- 

 previously begun. Near the close of the fiscal year arrangements 

 were made for hydrographic studies in Great South Bay, Long 

 Island, and for some oceanographic work to be done in the region 

 lying between Woods Hole and Long Island and from the coast out 

 to the Gulf Stream. The last-mentioned region has not been included 

 in other similar work done in recent years, and it is desirable to take 

 this up in order to fill in the gaps in our information. 



Rapid progress has been made with the reports dealing with the 

 oceanographic and biological survey of the Gulf of Maine. Thi& 

 work is being done by Dr. H. B. Bigelow, of the Museum of Com- 

 parative Zoology of Harvard University. Three reports are 

 planned, which together will cover the work accomplished. The 

 first paper deals with the fishes of the Gulf of Maine, their distribu- 

 tion, relative abundance, and such facts of their life histories as are 

 known. This report was in press at the close of the fiscal year 

 ending June 30, 1924, but has not yet been published. The second 

 report deals with the plankton of this region. The manuscript is 

 practically completed and will be presented for publication in the 

 very near future. The third report deals with the physical ocean- 

 ography. Considerable progress has been made with this report 

 and it is expected that it will be completed during the present fiscal 

 year. When completed, these three reports will provide a compre- 

 hensive survey of what is at present known of the phj^sical and bio- 

 logical factors influencing the distribution and abundance of the 

 food fishes of this region and will form a contribution of first impor- 

 tance to our knowledge of the fisheries. 



The hydrographic and biological survey of Long Island Sound 

 has been discussed under the section dealing with oyster investiga- 

 tions, since the survey bore particularly upon conditions as they 

 affected oyster culture. 



The work on the survey of Chesapeake Bay is well on its way 

 toward completion. A sufficient number of trips over Chesapeake 

 Bay, covering important stations at definite intervals of time have 

 been made and the results of collections and physical observations 

 are being prepared for publication. 



Reports from the following specialists are now in the hands of 

 Dr. R. P. Cowles: Leeches, by Dr. J. P. Moore; ascidians, by Dr. 

 Willard G. Van Name; echinoderms, by Dr. Hubert Lyman Clark; 

 sponges, by Dr. H. V. Wilson; annelids, by Dr. A. L. Treadwell; 



