AN AMPHIOXUS FROM JAPAN. 103 



Bingo, one of the members of the expedition, Mr. Ishikawa, discovered 

 larvae of Amphioxus amongst the material obtained by surface collecting. 

 In the same year Mr. Matsubara dredged Amphioxus off the coast of Buzen 

 (in the western part of Japan on the island of Kiushiu). Three or four 

 yeass ago Mr. H. Nakagawa, now Professor in the Higher Middle school of 

 Kumamoto, dredged several Amphious at Shigashima in the neighborhood of 

 Fukuoka, in the Province of Chikuzen (Kiushiu). This place has since 

 become the most reliable location for getting Amphioxus in Japan.^ 



An examination of sections of some of the above six specimens sent 

 from Japan shows that they agree closely in their general anatomy with the 

 common Amphioxus of Europe, the form known as B ranch iostomum 

 lanceolahim. Though thus agreeing in internal structure and presenting no 

 new anatomical aspects of interest as fur as observed, they differ in external 

 characters and are undoubtedly specifically distinct. The general outlines 

 and proportions of the body and fins, the number and arrangement of the 

 muscle segments, which determines the relative position of anus and 

 atriopore, and length of tail are the characters commonly regarded as of 

 systematic value and it is in these that the Japanese form dose not agree 

 with the European, 



Upon such characters a number of more or less satisfectory species have 

 been based, often enough from dead specimens poorly preserved. 



Accepting these for the present, in the absence of better, we may 

 summarize the characters of the lancelets thus far described by means of the 

 following table, 



1) Branch iostomum lanceolatum, 36. 14. 12-61, 43 mm. 



2) „ carihaeum, 35. 14. 9-58. 43 

 8) „ cultellum, 32. 11. 10-52. 23 



4) „ hassanum, 44. 14. 17-75. — 



5) „ Belcheri, 37. 14. 14-65. 65' 



6) „ elongatum, 49. 18. 12-79. 60 



7) ,, calif orinense, 44. 16. 9-68. 70 



' Quite recently Mr. Nakagawa has discovered another locality still more favorable for 

 obtaining AmiMoxus : Gosho no Ura in the Amakusa Sea, Kiushiu. 



