ONCOCEPHALUS PORRECTUS. 87 
front aspects, but in function are turned out and down to bring into view 
their hinder surfaces. From the recess there is a groove down and forward, 
narrowing toward the jaws, to bring the illicium in front of the mouth. 
Mouth medium, distant from the rostrum about the width of the orbit, a 
little farther forward than the illicial niche, obliquely rising forward. 
Teeth in villiform bands on jaws, vomer, palatines, and tongue. Eye lateral, 
of medium size ; orbit little more than half as long as the snout, two thirds 
of the width of the interorbital space. Nostrils small, close together, 
between the orbit and the forward end of the upper jaw ; anterior porelike, 
posterior larger, oblong, oblique. Gills two and one half, no gill on the 
first arch; rakers represented by low rather wide prominences, of which 
there are four on the first arch; gill openings small, placed superiorly in 
the axilla. Vent little backward of the middle of the entire length. 
Skin above and below thickly mailed by minute closely set stellate based 
tubercles amongst which on the upper surface there are scattered large tuber- 
cles the swollen trunks of which are harsh with small short spines arranged 
more or less regularly in radiating series. A series of the large tubercles 
passes from each side of the top of the snout along each side of the head 
and the median vertebral line to the caudal. Besides the upper two series 
there are three others at each side of the tail. Three series appear along 
each lateral edge of the disk, and also a number of scattered tubercles are 
seen between the dorsal and the lateral series. The largest tubercles are a 
pair, one of which stands in front of each eye; there is a smaller one above 
each orbit, and there are two between the orbit and the nape on each side. 
All of the tubercles have short stout cusps, with the general firmness and 
harshness of armature, the most serviceable ina rocky habitat. Lateral 
system indistinct on the top of the disk, less so on the sides of the tail, 
in a shallow groove below the front and the lateral edges of the disk. In 
many cases the papillee are entirely covered by a bridge formed by juxtaposi- 
tion of the apices of the two protecting spines. Filamentary fringes not 
greatly developed on the line; larger ones are scattered below the chin and 
along the carine of the tail. 
Olivaceous, more or less clouded on the back, white on the lower sur- 
face; a darker blotch on each side near the foremost vertebra, most often 
lighter in the centre; an ill defined streak of brownish passing back above 
the gill openings on the sides of the tail; fins blackish toward the ends, 
excepting the ventrals; a light band with brown at each side from each eye 
