4 ART. 11. — S. TANAKAi 



notch to the end of caudal filament is equal to the length of 

 body. 



Pectoral pointed and slightly falcate, with a deep notch at 

 its lower insertion in the fleshy base ; its tip reaches far behind 

 the insertion of ventral when depressed. Insertion of the ventral 

 midway between tip of head and notch of second dorsal, its tip 

 subtruncate, its inner margin rounded. Distance between origin of 

 second dorsal and insertion of pectoral a little shorter than the 

 distance between the latter and the insertion of ventral. 



There exists no difference in external features between the male 

 and the female except in the sexual characters. Cephalic organ 

 in the male directed forwards and downwards, situated on the 

 snout in front of the anterior margin of the eye ; its length 2 

 in eye ; on its lower side about sixty or more recurved spinous 

 denticles, very much like those of phantasma or mitsukurii. 

 Clasper tripartite ; its tip covered with fine shagreen as usual ; 

 its length from the insertion 1 i in head ; its division at a point 

 two-thirds of its length, as in purpurascens and owstoni (PI. I., 

 fig. 3), but unlike phantasma in which the point of division is 

 at one-third of the length (PI. I., fig. 4), while in mitsukurii the 

 clasper is rather short, bipartite, and the point of division situated 

 halfway of its length. In a young specimen, which measures 

 42.5 centimetres in total length exclusive of the parts behind 

 the dorsal notch and in which the cephalic organ is still em- 

 bedded in the skin, the claspers measure 1.6 centimetres in 

 total length and 1 centimetre in the length from the insertion 

 to the point of division ; they are already tripartite. In a 

 young phantasma 35 centimetres long and with the cephalic 

 organ still embedded in the skin, the claspers are still bipartite. 

 Ill all the Japanese species I have found the anterior ventral 



