Biological Survey — Oswego Watershed 171 



were clear and low. Careful observations were made for several 

 miles along the main inlet to the lake where the spawning occurs 

 both during and immediately after the spawning season was over, 

 and then some weeks after. In the silt along the edge of the 

 stream, and in the brush and other obstructions that catch floating 

 objects many dead lampreys were found. In dislodging the drift 

 in a brush obstruction in 1911, a couple of weeks after the spawn- 

 ing was over, several long whitish bodies were found. They looked 

 like very long round-worms. Investigating further these were 

 found attached in some cases to a partly decayed lamprey. It 

 was soon realized that these round-worm appearing bodies were 

 the notochords of the decayed lampreys. These notochords seem 

 to be the most persistent part of the lampreys, and they may be 

 found at least a month after the lampreys have died. Since 1911 

 notochords have been found every favorable year including 1927. 

 Also this year Mr. J. R. Greeley found them in the Beaverkill, a 

 tributary of the Delaware, where the large sea lampreys spawn. 

 As some of them were connected with partly decayed lampreys 

 there was no doubt of their character (Fig. 4*). 



The persistence of the notochords in the spawning streams has 

 been somewhat emphasized because if they were found by a 

 naturalist or a fisherman entirely separate from any part of a 

 lamprey they would certainly be a puzzle. In case a paleonto- 

 logist were to find a fossil notochord what would he call it? 



All of the above evidence for the death of the lampreys after 

 spawning makes the statement seem wholly justified that all the 

 lampreys spawn but once, and that after spawning they die. No 

 doubt death is not due wholly to starvation, although none of 

 them take food during the spawning time, but there are many 

 contributory factors. In attaching to each other by the sucking 

 mouth, the epithelial protection is removed leaving an opening for 

 infections of various kinds, the most common being the mold, 

 Saprolegnia. Even the large lake lamprey, may be almost covered 

 with it, as described for the brook lamprey above. 



In passing it may be added that the lampreys seem to be subject 

 to the ordinary defects that mar even the highest in the animal 

 kingdom. For example, something happened to one specimen, 

 for its oral disc was imperfect ; another had but a single eye and 

 another a single kidney, and still another only an excuse for a 

 tail. Only one albino larva was ever found, all the other lampreys, 

 young and old were properly pigmented. Taking it by and large, 

 the lampreys on the spawning grounds are quite perfect physically. 

 Probably the weaklings are ground to dust by the all-prevailing 

 law of the "survival of the fittest." 



