REPORT OF COMMISSIONER OF FISH AND FISHERIES. CXLI 



bearing on the practical work of the Commission, they are nevertheless 

 worthy of encouragement, because of their important bearing on the 

 physiology and i^athology of man; and the Commission considers it 

 not irrelevant to its functions to thus aid in the increase of knowledge 

 by furnishing for such inquiries a part of the wealth of marine life that 

 is obtainable at the laboratory. 



The clam industry of the northeast coast has for several years shown 

 an unmistakably downward tendency, and, next to the lobster, the 

 clam is perhajis the most important animal obtained in the shore fish- 

 eries now demanding consideration. An essential step preliminary to 

 the measures for increasing the clam supply is a thorough knowledge 

 of the breeding habits of the clam, its rate of growth, time of sexual 

 maturity, food, enemies, etc., on all of which subjects a survey of the 

 literature reveals a deplorable lack of information. In the summer of 

 1898 Prof. J. L, Kellogg was engaged by the Commission to give special 

 attention to this subject, and he has carefully examined the clam beds 

 in the Woods Hole region, at Essex, Mass., and in Narragansett Bay. 

 His studies have shown among other things (1 ) that there is an abun- 

 dance of young clams, the shores in July being literally covered ; (2) that 

 these young clams are destroj^ed by young star-flsli, which make their 

 advent on the shores at about the same time the clams appear; (3) that 

 young clams are easily susceptible of artificial rearing; and (4) that their 

 rate of growth is rapid. With these data, the Commission has under- 

 taken artificial clam-culture on an experimental but nevertheless rather 

 extensive scale, and the results so far obtained fully warrant the effort. 



Prof. Edwin Linton, whose investigations at Woods Hole have 

 greatly increased our knowledge of parasitology, continued his studies 

 of the entozoa of marine fishes. The large trap operated by the Com- 

 mission furnished abundant material for this work. It is important 

 that the fish-culturist should be acquainted with the fish parasites that 

 may invade the hatchery, but it is more important that the Commission 

 should have a knowledge of the life-history of all animals that spend a 

 portion of their lives in fishes and may finally infect man. 



Dr. A. D. Mead pursued several important lines of inquiry. In the 

 summer of 1898 he continued his observations on the star-fish begun 

 at the laboratory in the spring in the interests of the Rhode Island Fish 

 Commission. His work related especially to the habits, rate of growth, 

 powers of regeneration, and methods of breeding of the star-fish, which 

 ravages the oyster-beds of southern ]S"ew England and New York and 

 extends its depredations to the clam and mussel beds. A feature of 

 these investigations, which showed a positive relation between the 

 menhaden fishery and the oyster industry, was most instructive. That 

 the wholesale seining of menhaden, more especially in the inshore 

 waters, has a direct bearing on these ravages of the star- fish was not 

 suspected until the researches of Dr. Mead, carried on at Woods Hole 

 and in Narragansett Bay, i^roved beyond a doubt that the young of the 

 star-fish, at times so abundant that they actually color the water, are 



