28 



ON THE LAMPREYS OP JAPAN AND SIBERIA. 



provided with 2 well separated obtuse cusps ; the infraoral lamina posses- 

 ses 6 obtuse cusps. 3 bicuspid teeth are found on each side of tbe gullet. 

 Other buccal teeth are simple and describe a circle immediately inside of 

 the fringe of the labial tentacles. Each labial tentacle is palmate, termi- 

 nating in a blunt point. The specimen is female, but wants the anal 

 lobe (the fin-like appendage), probably owing to being caught out of the 

 spawning season. Coloration is quite like the Japanese specimen of L. 

 mitsukurii. 



The specimen is thus very close to L. mitsukurii of Japan ; io fact, 

 both are, I think, of the same species. It is, therefore, also very close to 

 L. loilderi (Gage) of North America. 



Let as now examine other species of the Lamprey of East Siberia. 



I have not seen the description of the Lamprey of Kamtschaka by 

 Pallas; 1 ) but by the account of Dr. Jordan, 2 . 3) I know that two 

 species of the Lamprey, Eutosphenus camtschations (Tilesius) and 

 Lampetra camtschatica (Pallas), are found in Kamtschaka. On the 

 former species he remarks : " A larval lamprey obtained by Stejneg-er 

 in the Paratunka River, near Petropaulski, Kamtschaka, is apparently of 

 some species of Eutosphenus. It can not be distinguished from the larva 

 of Eutosphenus tridentatus, though the adult may show peculiar charac- 

 ters " (p. 434). Eutosphenus tridentatus is, according to Jordan, common 

 southward along the coast of Unalaska. The auther puts the second 

 species (Lampetora camtschatica) synonymous with Lampetra aurea 

 (Bean), which is found also in the Yukon River and other streams ol 

 Alaska. Thus the two species, Eutosphenus tridentatus and Lampetra 

 aurea, occur common on the two continents, Asia and North America, 

 separated by the Behring Strait. 



Lampetra aurea is, according to Jordan, very close to Petromyzon 

 fluviatilis of Europe, and therefore, also to the larger Lamprey (L.japon- 

 ica) of Japan. 



1) . Paixas, Zoographia Rosso-asiatica, 1767. 



2) . Jordan, Report of Fur-Seal Investigations, Part. 3, 1899. 



3) . Jordan & Evermann, Fishes of North anil Middle America, Pt. I., 1899. 



