6 THE VOYAGE OF H.M.S. CHALLENGER. 



of the length of the prseoral portion of the snout. The labial fold extends a little way 

 along the margins of the mouth. Upper lip fringed. Pectoral short, with the lower 

 ano-le rounded, not produced. The first dorsal fin small, its base (without spine) is shorter 

 than that of the second, and nearly one-sixth of the distance between the two fins. 

 Spines very small, scarcely projecting beyond the skin. Extremity of the ventral 

 fins below the end of the second dorsal. The scales are tricuspid, with a median keel, 

 and so minute as to give a velvety appearance to the skin. Uniform deep black. 



Habitat. — Off Inosima, Japan, Station 232 ; depth, 345 fathoms. One specimen 

 (adult female), 27 inches long. 



The structure of the intestinal tract does not essentially differ from that of the ordinary 

 littoral or pelagic Selachian type. The stomach consists of two portions ; the anterior is 

 much the larger, of an elongate form, narrowed towards its posteiior extremity ; it passes 

 by an abrupt bend into the second reverted portion, which is the narrowest part of the intes- 

 tinal tract. The commencement of the intestine is a wide diverticulum, separated from the 

 stomach by the circular pyloric valve. The intestine proper is almost straight ; the spiral 

 valve commences on the level of the posterior extremity of the stomach, the spire being 

 composed of fifteen transverse gyrations. Csecal appendage worm-shaped, nearly an inch 

 long, with a very narrow cavity. The intestinal tract contained nothiiig but the single 

 beak of a cuttle-fish. The liver consists of two extremely long and flat lobes extending 

 on the right as well as on the left side from the anterior to the posterior extremity of 

 the abdominal cavity. Anteriorly they are connected by a short transverse strip not 

 broader than the lateral portions, and having imbedded in its middle line a gall-bladder 

 of moderate size. The ovaries are paired, containing mature ova, three in the right half 

 and five in the left. In the oviducts no separate divisions can be distinguished, the 

 whole of their cavity being coated with numerous longitudinal folds, the edges of which 

 are beset with villi. They are confluent anteriorly, and attached in the median line to 

 the ventral side of the abdominal cavity; their single opening is directed backwards 

 towards the Fallopian tubes and surrounded by a thick swollen j)ad of soft membrane, 

 the surface of which is finely transversely lamellated. ^ 



The valves of the conns arteriosus of the heart are arranged in five transverse 

 series, each series consisting of three principal valves and as many intermediate smaller 

 ones. 



Centroscyllium, M. and H. 

 Centroscyllium fabricii, Reinhardt. 



This Greenland shark has recently been discovered otf the const of Massachusetts, 

 whence the British Museum received through the Smithsonian Institution a specimen 

 captured in 250 fathoms. 



