286 THE PLAGIOSTOMIA. 



Syrrhina exasperata. 



Platyrhina exasperata Jordan & Gilbert, 1880, Proc. U. S. nat. mus., 3, p. 32, 53. 



Zapteryx exasperata Jordan & Gilbert, 1880, Proc. U. S. nat. mus., 3, p. 53; Jord. & Everm., 1896, 



Bull. 47, U. S. nat. mus., p. 64. 

 Trigonorhina alveata Garman, 1880, Bull. M. C. Z., 6, p. 169. 

 Syrrhma exasperata Garman, 1881, Proc. U. S. nat. mus., 3, p. 521. 

 Rhinobatus exasperatus Jordan & Gilbert, 1883, Bull. 16, U. S. nat. mus., p. 63. 



Disk wider than long, without the ventrals; snout short, broad, truncate. 

 Rostral cartilage stout, wide, not tapering; ridges nearly parallel. Nostrils 

 transverse, nearly as wide as the interspace; anterior valve slightly extended 

 beyond the nostril at the inner end; outer section of posterior valve narrow, 

 curving forward around the end of the nostril. Mouth large, bow-shaped, width 

 two thirds of the length of the snout; teeth small, one hundred and ten series 

 on the upper jaw of a male of 33.4 inches. Spiracle large, fold rudimentary or 

 absent. Pectorals large, broad, and rounded posteriorly, not extended beyond 

 the nasal region into the snout. Ventrals close to the pectorals; claspers long, 

 slender, with a knob at the end. Dorsals equal, tips rounded, hinder margin 

 straight, inner angle blunt; base of first dorsal more than twice its length behind 

 the bases of the ventrals, nearly twice its length from that of the second dorsal. 

 Tail less than one and one half times the length of the body, with a low dermal 

 fold along each side; axis of caudal not raised; subcaudal fin shorter, with a con- 

 vex margin. Scales small, with larger ones thickly scattered over the back, 

 about the eyes, and on the rostral ridges. Larger tubercles, almost covered by 

 the skin and scales, in a median series on the back and in two short rows on each 

 shoulder the outer one of which is longer. 



Greyish or olive-brown with indefinite and irregular transverse bands of 

 brown across the snout, in front of and between the eyes, and across the back 

 and the tail. Dorsals and caudal with faint bands or blotches. Lower surfaces 

 white with a large spot of blackish below the end of each pectoral. 



Specimen described from San Diego, California, secured by the Hassler 

 Expedition. 



Syrrhina xyster. 



Syrrhina exasperata Jordan & Gilbert, 1882, Proc. U. S. nat. mus., 5, p. 621. 

 Zapteryx xyster Jord. & Everm., 1896, Bull. 4'/ , U. S. nat. mus., p. 65. 



This species is said to have the disk broader than long, to have the same 

 coloration as the preceding species, and also to have several round black-edged 

 yellowish spots as large as the pupil; one on each side of the shoulder, another 



