1903.] NATURAL SCIENCES OF PHILADELPHIA. 169 



CEPHALAOANTHID^. 



6. Cephalacanthus spinarella (Linnaeus). 



1758. [Gasterosteus] Spinarella Linnaeus, Syst. Nat., Ed. X, p. 297; India. ^ 

 1866. Dactylopterus orientalis Playfair, Fishes of Zanzibar, p. 49; Aden; 



Zanzibar. [No descr.] 

 1893. Dactylopteru!^ orientalis Pfeffer, Jahrb. Hamburg. 'NViss. Anst., X. 



p. 12; Sansibar. [No descr.] 



Head 3f ; depth 5; D. I-I-6-S; A. 6; P. 31 : A'. 5; scales, in a lateral 

 series to the base of the caudal 50, and about 28 in a transverse series 

 between the spinous dorsal and the middle of the belly ; width of head 

 lyV in its length; depth of head H; snout 2 J; eye 2f ; maxillary 2f ; 

 width of mouth 2|-; mandible 2f ; interorbital space lyo ; least depth of 

 caudal peduncle 4+; first dorsal spine 1^; second 3^; third If; first 

 dorsal ray 1^; base of soft dorsal H; base of anal 2f ; ventral l^. 



Body elongate, depressed, the greatest depth about the base of the 

 ventral. Caudal peduncle broad, depressed, about as wide as deep at 

 its least depth. 



Head large, broad, and the greatest width a little less than the great- 

 est width of the body, which is at the bases of the pectorals. The upper 

 profile forms obtusely above the front of the eye. Snout broad, blunt, 

 rounded and projecting beyond the jaws. Eye large, nearer the tip 

 of the snout than the gill-opening in profile, and with the marginal 

 bones large and strong. Mouth inferior, much broader than long, and 

 the maxillary hardly reaching below the middle of the orbit. Lips 

 rather thick. Teeth fine, minute, and in bands in the jaws, none on the 

 vomer or pa'atines. Tongue broad, short, angular, and not free from 

 the floor of the mouth. Upper jaw produced beyond the mandible. 

 Nostrils close together, with slightly raised rims, and the space be- 

 tween the anterior pair, which are closer together than the others, about 

 two-fifths the interorbital space. Interorbital space very broad and 

 deeply concave. Surface of the head almost entirely rugose, and the 

 opercle and preopercle striate. Suborbital spine short, reaching below, 

 the upper margin of the preopercle, and forming a deeply dented 

 margin running up to the lower posterior rim of the orbit. Preopercle 

 ending in a \'ery long dagger-like spine reaching opposite the fourth 

 dorsal spine. Xuchal crests strongly ridged, with several denticula- 

 tions, and reaching posteriorly below the tip of the preopercular spine. 



Gill-opening rather small, lateral, its length al)out equal to the eye. 



Peritoneum pale. 



Scales strongly keeled, bony, and arranged in longitudinal series. 



-Based on [Ptingititis] pvsillus Linnaeus, Mvs. Adolph. Fred., 1754, p. 74, 

 Plate 32, fig. 5 (tliree figures). [Xo locality.] 



