18. PAORL's. 469 



a, h. 29" long : stuffed. Houtman's Abrolhos. 

 c, d. 22" long : stuffed. Houtman's Abrolhos. 

 e, f. Half-grown : skins. Houtman's Abrolhos. 



Skeleton. — The maxiUary bone is of nearly equal width in the 

 middle and at the extremities, and has the anterior edge slightly 

 emarginate ; the intermaxillary is joined to the posterior extremity 

 of the former, and has the posterior processes of moderate length, 

 rather shorter than the descending branch. The mancUbulary is some- 

 what elevated, with a narrow free interspace between the articular 

 and dentary pieces ; there are four or five distinct openings of the 

 muciferous channel, which runs along its lower surface. The head 

 of the vomei* is triangular, and has the anterior margins slightly 

 swollen. The turbinal bones are very long, tubiform, broadest pos- 

 teriorly, where they together form a suture, and divergent ante- 

 riorly, to receive the processes of the intermaxUlaries. The praeor- 

 bital is quadrangular, not much narrower posteriorly than anteriorly, 

 and one-third longer than wide ; the remainder of the infraorbital 

 ring is narrow ; there is a concave plate at its inside to support the 

 eyeball from beneath, and joined \o the entopterygoid by a hammer- 

 like pi-ocess. The axes of the limbs of the praeopercidum form an 

 obtuse angle ; the angle of the margin is rounded. There runs a 

 rather strong ridge parallel to the margins of the praeoperculum, with 

 a rudimentary muciferous channel and several disiinct foraminfe. 

 The operculum is irregularly quadrangular, with an interior ridge 

 descending obUquely in a backward direction. The suboperculum is 

 nearly vertically situated and pointed above ; the interoperculum 

 with the lower margin rounded. The frontal bones are rather flat, 

 obliquely situated, their highest point being at their meeting with 

 the occipital crest. The supraoccipital is horizontally situated, and 

 has a high triangular crest, the upper margin of which is swollen. 

 Of the lateral crests ihe outer one only is developed, and transformed 

 into a very distinct channel with about five openings. The base of 

 the skull is slightly compressed, and there is a wide cavity in the 

 basisphenoid before the occipital joint. The pubic bones are of mode- 

 rate length ; each is formed by three lamellae, the inner of whieh is 

 broadest. 



There are ten abdominal and fourteen caudal vertehrce, the length 

 of the former portion of the vertebral column being to that of the 

 latter as 1 : 1-4. There are three spurious interneural spines in front, 

 styliform ; nearly aU the others are dijated : the second is the longest, 

 the following gradually decreasing in length. The first interhaemal 

 is strong, and equal in length to the first seven vertebroe. Some of 

 the ribs have epipleural spines. 



There are foux canine teeth in both jaws. The molars are of 

 nearly equal size, and small ; two series in the upper jaw. In the 

 lower jaw they are arranged in two, series on the middle part only 

 standing in a single series anteriorly and posteriorly. 



