198 THE PLAGIOSTOMIA. 



rows: symphyseal upper teeth triangular, erect, from these the lateral become 

 more oblique and at the sides of the mouth resemble somewhat those of Squalus 

 acanthias, the cutting edge approaching the horizontal; on the lower jaws the 

 teeth are like those of S. acanthias, the cutting edges are smoother and more 

 nearly horizontal than those of C. granulosus. Eye large, length of orbit equal 

 the preorbital length of the snout, or three fourths of the distance to the first gill 

 opening. Spiracle rather large, crescentic, situated less than its diameter 

 behind the corner of the eye and as much above it. Gill openings wide, widening 

 and becoming closer together backward, hindmost one abruptly widest, hind- 

 most pair close together, in front of the pectoral. Pectorals large, outer angle 

 rounded and below the spine of the dorsal, inner angle much produced, but 

 hardly subtending the dorsal base. Dorsal spines strong, grooved longitudi- 

 nally on the sides, not as high as the fins, anterior exposed about one third and 

 posterior more than half of the length. Origin of the first dorsal above the axils 

 of the pectorals, end of base very little behind the ends of the pectorals, base 

 excluding the spine equal two sevenths of the interdorsal space. Second dorsal 

 about two thirds as large as the first, origin behind the axils of the ventrals, 

 hind angle produced and reaching behind the origin of the subcaudal. Ventrals 

 small, outer angle broadly rounded, hinder sharp, end below spine of the second 

 dorsal. Caudal little more than one fourth of the total length, rather deep; 

 subcaudal without a produced lobe, separated from the terminal by a shallow 

 notch. Scales small, rough, with a strong median and weaker lateral converging 

 keels; on the snout the scales are more sessile and when the crowns have worn 

 away the edges indicate a greater number of ridges; near the dorsal fins they 

 resemble those of Oxyrhina. 



Rusty brown, back little darker, lower surfaces whitish ; in young the edges 

 of the caudal and the paired fins are lighter ; inside of mouth dark. 



Total length of an immature male, from Nice, 20, snout to abdominal pores 

 lli snout to dorsal 6, snout to pectoral 4j, snout to mouth 2, and caudal 5j 

 inches. 



The outlines of the figure given by Bonaparte are excellent; the teeth 

 figured with it are those of a Squalus. 



This species is very distinct from others of the genus, But is a true Centro- 

 phorus, and cannot be placed in Squalus, as has been recently suggested by 

 Regan (Ann. mag. nat. hist., ser. 8, 2, p. 48), and previously by other authorities. 



