12G ON THE VARIATIONS OF THE PROPORTIONAL LENGTHS IN THE EEL. 



From these measurements it will be seen that all the specimens from Toku- 

 shima in the Island of Shikoku, are of the vulgaris type. The same is the case 

 with a single specimen taken in the river Asahi in Mimasaku, while coming over 

 to the northern side of the mountain range, we find among 5 specimens from the 

 Lake Jinzai, Idsumo, 1 bostoniensis, 2 doubtful spech standing between the 

 two, and 2 vulgaris. A similar state of things appears to occur in Lake Shinju, 

 a little way east of Jinzai. Here among four specimens, two are of the type 

 bostoniens!* and the other two of vulgaris. Further east in Tottori, Hoki, the bodo- 

 niensis type appears, to become less. Of the five specimens taken in the vicinity 

 of the town, one only proved to lie between the two varieties, while the four 

 others were of the vulgaris. In Saikawa, Imaegata, in the Province of ■ Kaga, 

 and in Lake Biwa, all lying further east from Tottori, we still find some bosto- 

 niensis. The vulgaris type appears, however, to preponderate more and more, 

 and in Tokyo, judging from only three specimens kept in the museum, we find 

 more vulgaris than bostonien sis. The same appears to be the case with the speci- 

 mens collected north of Tokyo. Of 21 specimens from Lakes Hirobuchi and 

 Shinai, both lying very near to each other, only 1 bostoniensis was found, while 

 all the others proved to be vulgaris. But further north in Lake Kogawara in 

 Rikuoku the bostoniensis appears to become more mumerous ; 3 out of the 10 

 specimens taken from that lake being bostoniensis while two stand between the 

 two varieties. Lastly the specimens from Hidaka in Hokkaido, show more 

 bostoniensis than vulgaris. 



The above tables are of course made from too few specimens to draw any 

 conclusion as to the distribution of the two types of Anguilla in our country. It 

 seems, however, that the type bostoniensis occurs more in the south-western and 

 in the northern provinces, while in the central portion, vulgaris is the prédomi- 

 nent type. 



Printed DeeemUr 30, 1S98. 



