NO. 1324. ELASMOBRANCHIATE FISHES— JORD AX AM) FOWLER. (327 



A gigantic shark from Japan has been described by Dr. Kishinouye 

 under the name of BJdnodon pentalhieatus. It is apparently a species 

 of Rhlneodon, but it is impossil)]e to say whether it is different from 

 RJi!neodo)i fypicius or Rhlneodoii jninctatus, or whether these two 

 nominal species differ from each other. Rldneodon typicus is widely 

 diffused in the tropical seas and has been lately taken in Florida, a 

 record having ])een published hy Mr. Barton A. I)ean. It is prol)ably 

 th(? only species of the genus. The following is Dr. Kishinouye's 

 description: 



Head Hat, ])lunt; eyes very small, situated on sides of head near 

 margin of colored area; nictitating membrane wanting; mouth neai'h' 

 straight, terminal; a labial fold runs fi'om nostril to corner of mouth 

 on upper jaw, and shorter fold from corner of mouth on lower jaw; 

 teeth very minute, numerous, nearly e(|ual in size and shape, each 

 acutely pointed, laterally compressed, and with an ellipsoidal root; 

 band of teeth in upper jaw curved a little, each end of band with a 

 detached group of teeth, l)and in lower jaw crescent-shaped, and in 

 each l)and arranged in a great many transverse row's, about 300 in niun- 

 ber, middle part of band with 16-30 teeth in one row; nostrils at 

 anterior extremity of head, and opening at labial boundary of mouth. 

 Gill-openings 5, very wide, the second pair widest, measuring Sd cm., 

 last pair most narrow, opening above base of pectorals, where body is 

 very broad and high. Spiracles nearl}' same size as eye and on the 

 same level. 



Skin tine grained, except tive longitudinal smooth bands, one dorsal 

 median, two pairs lateral; ventral lateral l)and seems to be continuous 

 with keel on each side of tail. 



First dorsal tin inserted a little behind middle of body; second dorsal 

 fin ver}' small; anal very small, just below second dorsal; pectorals 

 large, strong; ventrals inserted below tirst dorsal ; caudal large, lunate, 

 its ventral lobe well developed; clasper simple, with dorsal groove. 



Color grayish brown, with round white spots and transverse bands, 

 ventral side colorless; round white spots small and crowded near ante- 

 rior end of body, gradually larger and fewer backward; caudal, second 

 dorsal, ventrals, and anal destitute of white markings. 



Length at present 800 cm., in circumference behind pectorals, 365 

 cm. (stuffed specimen), but when fresh measuring nearly 1,000 cm. 



Taken in a drift net June 10, 1901, off Cape Inubo; now in the col- 

 lection of Tsurutame Oseko of Asakusa Park, Tokyo. (Kishinouye.) 



The Japanese form is ■ known only from the example described 

 above. When taken it was covered with many sucking fishes {Echeneis)^ 

 and one, besides an oak pole, was taken from its stomach. It is 

 said to differ from Rhinodon typicus Smith and Mhrlstodxs punctattis 

 Gill in the form of the teeth and the labial fold. But it is impossible 

 to distinguish species in this genus until its members are ))etter known. 



{typ/cKs, typical.) 



