292 



THE PLAGIOSTOMIA. 



Spiracles large, without folds. Scales unlike, minute, and larger. Dorsals small, 

 equal, rounded; origin of the first dorsal more than three times the length of the 

 base behind the bases of the ventrals. Caudal small, rounded; subcaudal not 

 lobed. Small tubercles in the vertebral series, above the rostral cartilage, on 

 the orbital ridges, above the basal cartilages of the pectorals and in a row of 

 three on each shoulder. 



Back brown with darker cross bands and with spots between them toward 

 the edges of the pectorals. Lower surfaces brownish, irregularly mottled with 

 brown. 



India. 



Mliller found an eggshell resembling that of a Catuloid shark in the oviduct 

 of the type specimen. Whether the egg is hatched before extrusion, as in cer- 

 tain Antacea, is still to be determined. 



Arhynchobatis. 



Arhynchobalis Waite, 1909, Rec. Canterb. mus., 1, no. 2, p. 20. 



Snout unsupported by a rostral cartilage; pectorals contiguous in front, 

 narrowly separated by the snout. Spiracles close behind the eyes. Anterior 

 nasal valves reaching the mouth, joined to the isthmus in a deep median notch; 

 posterior valves tube-like as in Raia. Tail long, depressed, with a lateral fold 

 on each side, with a single dorsal fin near the end, and with a well-developed 

 caudal fin. 



Arhynchobatis asperrimus. 



Arhynchobalis asperrimus Waite, 1909, Rec. Canterb. mus., 1, no. 2, p. 20, pi. 20. 



Disk little wider than long, front angle blunt, tip of snout a slight promi- 

 nence. Mouth moderate, slightly curved. Teeth small without cusps. An- 

 terior nasal valves subtriangular. Spiracles close behind the eyes. Back rough 

 with closely set small spines, larger on the head ; larger spines occur above the 

 shoulder girdle and the forward vertebrae. Strong tubercles appear in a median 

 row and several lateral rows on the tail. Dorsal small, near the caudal, space 

 between without spines equal dorsal base. Tail about half the total length, 

 depressed, with lateral folds; caudal fin well developed, near the single dorsal. 

 Length of type, a female, 64 cm., little more than 25.5 inches. 



Back uniform purplish grey; lower surface yellow. 



Bay of Plenty, New Zealand, from 66-94 fms. 



