ON THE VARIATIONS OF THE PROPORTIONAL LENGTHS 

 OF THE HEAD, etc. AS TO THE TOTAL LENGTH 

 IN OUR OMMON EEL 



By Dr. C ishikawa. 



Imperial University cf Tokyo. 



Some years ago while looking over the collection of eels from Lake Biwa, it 

 struck me that the amount of variations occurring among the individuals taken 

 from one and the same locality is very great, a fact -which induced me to con- 

 clude that the two species of eels — Ang. vulgaris and box'oniensis might simply 

 he varieties of a single species.* 



As I made these observations I was cpiite ignorant of similar and more ex- 

 tended observations of M. C. Darestef who came to the same conclusion long 

 before me, and it may therefore of be no use to beat over the same ground 

 again. But in order to see the exact amount of variations occurring among the 

 specimens taken from different parts of our Island, and to determine whether the 

 two varieties are peculiar to certain localities, the following measurements were 

 made : — 



* C. Is h ne AAV A : A Preliminary Note on the Fishes of Lake Biwa, Zool. Magazine Vol. 

 < II. No. 82. 1895. 



t Comptes-rendus of the Academy of Sciences, Paris. 



