216 



THE PLAGIOSTOMIA. 



First dorsal spine nearer to caudal than to end of snout 

 eye midway between end of snout and base of pectoral 

 teeth of lower jaws subhorizontal on cutting edges 



inner angle of pectoral shorter . . hystricosum (page 220) 

 eye nearer to pectoral than to end of snout 

 teeth with small basal cusps 



margin of pectoral rounded behind . eglantina (page 221) 



ACANTHIDIUM CALCEUS. 



Acanihidium calceus'Low'E., 1839, Proc. Zool. 8oc. London, p. 92; 1843, Trans. Zool. soc. London, 3, p. 19. 



Centrophorus calccus Lowe, 1843, Proc. Zool. soc. London, p. 93; Gunth., 1870, Cat. fishes Brit, mus., 

 8, p. 423; Vaillant, 1888, Travailleur et Talisman, Poissons, p. 71, pi. 3, f. 1; Moreau, 1891, 

 Poiss. France, Suppl., p. 132; Goode & Bean, 1896, Mem. M. C. Z., 22, p. 14; Collett, 1903, 

 Suppl. Norges fiske, 2, p. 21 ; Regan, 1908, Ann. mag. nat. hist., ser. 8, 2, p. 51. 



Centrophorus crepidalbus Bocage & Capello, 1864, Diag. fam. Squal., p. 2; Proc. Zool. soc. London, 

 p. 262, f. 2; 1866, Plagios., p. 28, pi. 2, f. 1; Capello, 1870, Jor. Acad. sci. Lisboa, 2, p. 144; 

 Bocage, 1872, Jor. Acad. sci. Lisboa, 3, p. 88. 



Scymnodon ringcns Goode & Bean, 1896, Mem. M. C. Z., 22, p. 11, pi. 4, f. 12 (non Bocage & Capello, 

 1864). 



Body elongate, subfusiform. Head depressed; snout very long, broad, 

 spatuliform, about half the length of the entire head, nostrils transverse, about 

 three fifths of the distance from the mouth to the end. Internarial width less 

 than one third of the preoral length of the head. Mouth wide, with a deep 

 groove and labial folds at each angle. Teeth not serrated, diverse; upper with 

 narrower more erect cusps, becoming oblique toward the angles of the mouth; 

 lower broader, with cutting edge oblique, more nearly horizontal. Spiracles 

 large, opening upward, less than the length of the orbit behind the eye. Gill 

 openings narrow, in front of the pectoral. Pectorals rather small, subtruncate, 

 hind angles rounded, not reaching below the first dorsal spine. Dorsal spine 

 about midway from snout to caudal, compressed, with a groove along each side. 

 Base of first dorsal without the spine little longer than the base of the second, 

 more than half the interdorsal space; end of fin acuminate. Second dorsal 

 higher than the first, spine nearly as high as the fin, base much longer than its 

 distance from the caudal, end of the fin reaching the latter. Axils of the ventrals 

 little in front of the spine of the second dorsal; fins small, narrow, ends below 

 middle of second dorsal. Tail short, about one third of the total length; caudal 

 short, subcaudal angle hardly produced. 



Scales minute, with a broad polygonal base and a slender erect peduncle 

 from the top of which the crown bends backward in three slender cusps. 



Ashy or greyish brown, uniform or clouded. 



Deep waters off Portugal and Madeira, 



