222 THE PLAGIOSTOMIA. 



Scales stout, erect, short 



width of head across the gills greater than the preoral length 



princeps (page 222) 

 Scales setiform, not forming ridges 



ventrals much nearer to the caudal than to the pectorals spinax (page 223) 

 ventrals equidistant from caudal and pectorals 



spine of first dorsal equidistant from mid orbit and second dorsal 



hillianus (page 224) 

 spine of first dorsal equi distant from end of snout and second dorsal 



rillosvs (page 225) 

 Scales setiform, forming longitudinal ridges 



ventrals of the male equidistant from the pectorals and the caudal 



caudal as long as the head lucifer (page 220) 



caudal shorter than the head . . . brachyurus (page 227) 



Scales placoid, with raised edges; 



spine of the first dorsal equidistant from the orbit and the second dorsal 



pusillus (page 228) 

 Scales placoid, with a central spine and with spinules 



spine of first dorsal equidistant from spiracle and second dorsal 



paessleri (page 229) 

 Scales granular anteriorly, setiform posteriorly 



spine of first dorsal equidistant from spiracle and second dorsal 



granulosus (page 230) 



Etmopterus princeps. 



Etmopterus princeps Collett, 1904, Forh. vid.-selsk. Chra., no. 9, p. 3; 1905, Rept. Norw. fish & mar. 



invest., 2, p. 29, pi. 1, f. 1-2. 

 Spinax princeps Regan, 1908, Ann. mag. nat. hist., ser. 8, 2, p. 44. 



"Head rather broad; length of snout (from mouth) less than the width 

 across the gill openings. Scales forming a short radiated spine, its height not 

 exceeding the base of the scale, and allowing the skin to be everywhere visible 

 between the scales. 



Gill openings. The anterior wider than the posterior ones, the width being 

 about twice the diameter of the spiracula. 



Color blackish brown; membranous margins of the fins bluish. 



Size large, total length reaching 728 mm. [about 28.6 inches]. 



Faroe Channel; Faroe Bank. Depth 750-1200 metres." 



