24 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



beldiiyini;- to each sidi- ol'tlic body) wliich liave coalesced. Though small and harsh to the 

 touch" the scales on the body nvv. not sharp; they otter about the same resistance from what- 

 ever direction the finger may be passed over them. On the tail, however, they are very 

 sharp and the points are directed backward. Along the edges of the canals on both body 

 and tail tiie scales are comi)ressed and flattened; they form the only cover or protection for 

 these organs, wliich in the specimen described have the appearance of long seams or grooves. 

 On the skull these canals do not stand open as on the rest of the body. Near the mouth, 

 and especially toward its angle, the scales are larger and more prominent. Under the 

 middle of the belly, the skin forms two closely approximated rolls or ridges separated by a 

 groove, and inside of these the muscle is thicker than towards the flanks. Intestine very 

 small, valve spiral. Abdominal pores opening behind the vent, protected by a fold. Car- 

 tilages sott and flexible as those of Somniosus or Selache. Uniform brown, darkei- at the 

 thin margins of the fins. 



This species was first described in 1884 from a specimen in the Museum of Comparative 

 Zoology, believed to have come from Japan. At this time it was suggested that it might 

 coirespond very closely to an animal 24 feet in length, observed in 1880 at Pemaquid, Me. 

 (Bull. U. S. Fish Com., iii, p. 407, cut), and that it was one of the forms which had been 

 discussed under the name of sea serpent. Giinther has since had three specimens, the 

 largest 4 feet 10 inches long, from Yeddo Bay. The Prince of Monaco found it near Madeira, 

 March, 1889. 



Order RAI.«. 



Selachians with pectoral fins much developed, and produced from the anterior margins 

 forward, and connected with the rostral cartilages, thereby constituting an integral part of 

 the form, and not abruptly differentiated from the body, as in the sharks and all true fishes; 

 the branchial openings are in two converging rows of five each on the inferior surface of 

 tlie body; spiracles are well developed behind the eyes. In other respects the order essen- 

 tially agrees with the Squali, and the two form a common superorder or subclass, the 

 Plagiostomi. The form varies considerably in the several members of the order; on the 

 one hand, the sawfishes have an outline much like that of the sharks, and with a long 

 caudal portion, and, on the other hand, the eagle rays and certain stingrays have a disk 

 extremely wide — much wider than long — and the caudal portion is reduced to a whip-like 

 appendage. These two forms exemplify the extremes of the characteristics according to 

 which the order is divided into two suborders, viz: (1) Pachyura (including the Raiida', 

 Rhinolxttida; rrintidd', and Torpediaidw) and (2) MasticubA, including the ''eagle rays" 

 [MijUohaUdm), "devil-fishes" {Cephalopterid(e), and "stingrays" {Trygonidfc). — (tHI. 



Of the several families which compose this order, only one, the lialidce, is represented 

 in the depths of the sea. 



Family RAIlDyE. 



Rajidw, (ittXTUEK, Cat. Fish. Brit. Mus., viii, 1870, 453. 



Disk broad, rhomboid, rough or spinous; tail stout, rather long, with a longitudinal 

 lateral fold, usually witli two dorsal fins and on some species a caudal fin; pectorals extend- 

 ing to snout; ventrals large; no serrated spine on the tail; oviparous; egg cases leathery, 

 with hollow tendrils at each of the four angles. 



RATA, Linnaeus. 

 Raia, LlNN^us, Syst. N.at., 1758, 231, cd. x; tyjio Itaia clavala, L. 



Raiidn, with pectoral fins not continuous around the snout, with ventrals deeply notched, 

 and caudal slightly developed or wanting; with tail quite distinct from the disk, and pro- 



