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REPORT OF THE COMMISSIONERS OF 



miles from the lake. We do not hesitate to say that we feel thoroughly convinced 

 that they do not attack fishes and, in fact, as stated, do not take food of any kind in 

 the adult state. 



The Brook Lampreys spawn from two to three weeks earlier than do the Lake 

 Lampreys, or when the water is yet from ten to five degrees (Fahrenheit) colder than 

 that in which the Lake Lampreys spawn. One of the most interesting accounts of 

 their spawning habits is by Dr. Bashford Dean and F. B. Sumner, in the Transactions 

 of the New York Academy of Science, Vol. XVI, December, 1897. It i s by kind 



No. 2. — MALE AND FEMALE BROOK LAMPREYS, ON SPAWNING BED. 



permission of tne authors that we reproduce the very excellent drawing of the Brook 

 Lampreys on their spawning bed (see illustration No. 2). The pair in the upper 

 part of the picture is in copulo, and each of the two in the lower corners is trying to 

 move a stone many times its own weight. Such a feat is, of course, impossible, 

 although we have seen representatives of both species found here move stones 

 thrice as heavy as themselves. We know that these lampreys do not come up the 

 stream in numbers to spawn, as do the Lake Lampreys, as they were seen in immense 

 numbers on the gravel above our weir after it was perfectly constructed of wire 



