EEPOET OF COMMISSIONEE OF FISH AND FISHEEIES. 137 



jointly by Professor Tower and Mr. E. H. Green, and a special report 

 thereon was published in the 1901 Bulletin. Numerous gallstones 

 were found in several of the squeteague caught in the pound nets, and 

 the determination of the chemical constituents of the calculi formed the 

 subject of a paper by Professor Tower and Mr. A. K. Krause, forming 

 a part of the 1901 Bulletin, which is an important contribution to the 

 diseases of wild fishes. A related subject which received attention was 

 the bile pigments and bile acids of squeteague, blue-fish, and bonito. 



In the course of a general study of noises produced by fishes, some 

 important physiological observations were made on the "drumming"" 

 of the squeteague. The drumming of the drum-fishes {Scidenidai), of 

 which the squeteague is the most prominent representative at Woods 

 Hole, has been variously explained by difierent writers; and in the case 

 of the squeteague, at least, it would appear that no accurate account of 

 the factors producing the characteristic sound has heretofore been 

 given. 



Professor Tower's observations and experiments have developed the 

 following facts: 



1. There is in the squeteague a special drumming muscle, lying 

 between the abdominal muscles and the peritoneum, and extending the 

 entire length of the abdomen on either side of the median line. 



2. The muscle fibers are ver}^ short, and run at right angles to the 

 long axis of the muscle. 



3. The muscle is in close relation with the large swim-bladder, and 

 b}^ its rapid contractions produces a drununing sound, with the aid of 

 the tense bladder which acts as a sounding-board. 



4. This muscle exists only in the males, and only the males are able 

 to drum. 



In continuation of the plan of issuing from time to time systematic 

 reports on the various groups of water animals in the Woods Hole 

 region, studies of the following groups were carried on during the 

 year: The crabs, by Dr. Robert P. Bigelow, of the Massachusetts 

 Institute of Technology; the jelly-fishes and sea-anemones, by Prof. 

 Charles W. Hargitt, of Sja-acuse Universitj^; the parasitic copepods 

 of fishes, Iw Mr. M. T. Thompson, of Brown University, and Mr. C. B. 

 Wilson, of the Westfield (Massachusetts) State Normal School; the 

 isopods, by Miss Harriet Richardson, of Columbian University (Wash- 

 ington, D. C); the amphipods, by Prof. S. J. Holmes, of the University 

 of Michigan 



Following is a list of those in attendance at the laboratorj'-, arranged 

 under the institutions with which they were connected: 



U, S. Department of Agriculture : W. T. Swingle, Ph D. ; Dr. Geo. T. Moore; Karl 

 Kellerman, B. S. 



Brown University. R. W. Tower, A. M. ; L. W. Williams, Ph. D.; George H. Sher- 

 wood, A. M.; M. T. Thompson, A M. ; A. K Krause, A. B. 



Brijn Mawr College: T H. Morgan, Ph. D. 



Columbia University Gary N. Calkins, V\\ D. 



