458 Simon Henry Gage 



and fishes to which it attaches itself. He is followed by 

 nearly all authors, more especially in describing the food of 

 the brook and river lampreys. From personal observations, 

 the food of the brook lamprey of the lake region has not been 

 determined, as none have been taken out of the breeding 

 season except those which were transforming. From their 

 small size (150-200 millimeters) and the probable shortness of 

 adult life, the injury to the larger food fishes in any case must 

 be considered slight. This is especially true of the region 

 under consideration, for in addition to the smallness in size 

 and probable shortness of life, they are few in number. While 

 it is not at all difficult to get 200 to 400 lake lampreys from 

 the Cayuga Lake inlet during one spawning season, one must 

 work quite persistently to obtain 75 to 100 brook lampre3-s. 



With reference to the usefulness of the brook lamprey in 

 New York, it may be put down as nil. In England, accord- 

 ing to Couch ('65) and Seeley ('86), the adult river lampre}' 

 which is very closely allied to the brook lamprej% or speci- 

 fically identical with it (Schneider, '79, Shipley '87), was 

 formerly much used in the cod and turbot and other deep sea 

 fisheries. It is stated by Seeley that the lamprey fishery be- 

 gins in August and continues till March, and that in that time 

 as many as 450,000 have been taken and used as bait in one 

 year. 



With reference to the lake lamprey, the conditions are quite 

 different from those described for the brook lamprey. In the 

 first place the lake lamprey exists in large numbers, and lives 

 a parasitic life from one and a half to three and a half years. 

 Of all the specimens obtained out of the breeding sea.son, 

 either the digesting part of the alimentar}^ canal was emptj* 

 or it contained blood. No partly digested worms or insects or 

 small fish or fish fiesh were ever found, although diligent 

 search was made ; consequently it is believed that the lake 

 lamprey is wholly parasitic during its adult life and lives on 

 the blood sucked from other fishes. From the structure of 

 the mouth and the opening to the oesophagus in the adult, one 

 might also infer that liquid food was used and that this was 

 obtained by suction as with a leech. 



