39. PENXACEROS. 213 



triangular space between the ventrals and the throat much narrower 

 than long. Yellowish, marbled with brown. 

 Cape of Good Hope. 



8. Pentaceros decacanthus. (Plate XV. fig. A.) 

 D. ^. A. ^. 



• 13 ' 8 



The height of the body is one-half of the total length, the length 

 of the head not quite one-third. Ventral spine very thick and strong. 

 The triangular space between the ventrals and the throat as broad 

 as long. Yellowish, marbled with brown. 



a. Has been dried. Pacific. Voyage of the Herald. 



Description of the specimen. — In general appearance this species 

 much resembles the preceding, but it is still higher, and the much 

 greater breadth of the breast gives a very good distinctive character. 

 The outline of the lower profile is horizontal from the jaws to the 

 anus ; behind the vent it suddenly rises to near the caudal fin ; the 

 upper profile is very curved, but does not descend so far behind as in 

 front. The eye is placed high up the sides, without interfering with 

 the ilpper profile ; above its middle a spinous process projects from 

 the frontal bone, and there are, besides, several very small spines in 

 front of the larger one. The diameter of the eye is nearly one-third 

 of the length of the head, and equals the interspace between the eyes. 

 All the upper surface of the head appears to be bony, without being 

 covered by a soft skin ; it is striated, the streaks radiating from 

 a centre above each eye. The nostrils are close together, one before 

 the other, and placed immediately in front of the upper angle of the 

 eye : the anterior is very small, ovate ; the posterior larger, round. 

 The snout is rather shorter than the diameter of the eye ; the cleft of 

 the mouth is very oblique ; the lower jaw prominent. Both the jaws 

 are armed with bands of fine vilHform teeth : a small patch of 

 vomerine teeth is distinctly visible, but I am unable to see further 

 to the palatine bones. The upper maxillary does not appear to reach 

 the front edge of the orbit, and may be partly hidden beneath the 

 anterior suborbital bone ; this is large, and armed with several 

 strong denticulations below, and vdth very small ones at its orbital 

 margin ; the remainder of the infraorbital arch is not denticulated. 

 There is a rhomboidal bone with a prominent longitudinal ridge on the 

 occiput. All the bones of the humeral arch and the opercles are 

 strongly striated. The scapulary has a prominent ridge terminating 

 in a spine. The operculum is entire and has a waving margia ; the 

 praeopercidum has a rounded angle and is denticulated throughout, 

 the spinous teeth being stronger beneath. Cheeks scaly. The gill- 

 opening is wide ; but I cannot count the branchiostegals on accoimt 

 of the condition of the specimen. 



The pectorals are inserted at the lower third of the height of the 

 body ; they are pointed, and appear to reach to the vent. The 

 ventrals are very remote from each other ; their spine arises just 



