RA YS — CHIMERAS 365 



birth to fourteen young ones, which were spotted as conspicuously as a leopard, 

 whereas in the adult the spots are much less distinct, and in some cases are formed 

 by the agglomeration of pin-like dots. Among the sting-rays and the allied 

 butterfly-rays of the Indian and other tropical oceans, the genus Trygon 

 is represented by numerous species such as T. pastinaca, which occurs not un- 

 commonly off the British coasts, while T. seplien and T. walga are much larger 

 Indian species. Severe lacerated wounds are caused by the serrated tail-spines of 

 these rays. Other Indian genera are Urogymnus and Astrape. Very remarkable 

 is an Indian ray described as Bengalichthys, which was discovered a few years ago, 

 and is distinguished from Astrape by its thickened and fleshy disc, the rudimentary 

 pectoral fins, and the degenerate eyes. Another genus of rays, Dactylobatus, has 

 recently been established, for a species of which two examples were taken off South 

 Carolina a quarter of a century ago. The generic name refers to the presence of a 

 finger-like process jutting from the middle of each pectoral fin, which, together with 

 the subcircular form of the disc, distinguishes this handsomely spotted species from 

 the typical rays of the genus Raid. 



Sharks and rays collectively constitute the group Elasmobranchii. 

 Another group of cartilaginous fishes, the Holocephali, differing 

 remarkably in the structure of the skull, is represented by those strange and 

 interesting fishes the chimasras. That they have certain relationships with the 

 sharks and rays is admitted by all, although there is still some diversitj 7 of opinion 

 as to the closeness of this affinity. Chimseras, of which the typical Chimcera 

 monstrosa is the longest known species, include several genera, and are somewhat 

 shark-like fishes, with blunt muzzles, terminal mouths, large eyes, long, triangular 

 pectoral fins, high first dorsal fins, with a spine in front, short bodies, a whip-like 

 termination to the long compressed tail, and a silvery skin. Their dentition 

 includes two pairs of large, flattened, dental plates above and one below. The 

 genus Callorhynchus differs from Chimcera, which has been referred to in an 

 earlier chapter, by the presence of a peculiar appendage to the muzzle. Chimseras 

 abound in Japanese waters, where they are represented, among others, by Chirruera 

 phantasma and G. mitswkwrii. Of the former species it is stated that while some- 

 times the fishermen will catch from twenty to thirty specimens a day in water 

 varying between 50 and 300 fathoms in depth, on other occasions they do not find 

 a single example for days. Although sluggish in their movements when kept in 

 baskets in shallow water (where they soon die), there is reason to believe that in 

 their normal haunts these fishes display considerable activity. Their peculiar egg- 

 cases are larger than those of any other species. Japan is also the home of the 

 long-snouted chimsera (Rhinochimcera paxifica) which has been made the type of 

 a genus by itself, although doubts were soon after entertained whether it was 

 generically distinct from a species previously named Harriotta raleighana, the 

 first known example of which was taken in deep water near the Bermudas in the year 

 1905. A second representative of the same genus, Rhinochimcera atlantica, is known 

 by a specimen taken off the south-west of Ireland at a depth of between 670 and 770 

 fathoms. Both these long-snouted fishes diner from the ordinary blunt-headed 

 chimseras by the production of the upper jaw into a long, spear-like beak, and the 

 replacement of the elongated, whip-like tail by a much shorter and deeper caudal 



