FISHES BATEACHIDAE PORICHTHYS NOTATUS. 135 



The largest specimens which we have before us measure about nine inches and a half in total 

 length, the head forming the fourth part of it, the caudal fin excluded. The body is sub- 

 cylindrical anteriorly, compressed, rather more so posteriorly, and tapering very regularly 

 towards the insertion of the caudal fin. 



The eye is rather small and situated near the upper surface of the head ; it is sub-circular in 

 shape, and its longitudinal diameter is contained six or seven times in the length of the side of 

 the head. The mouth is very broad viewed in front, not very deeply cleft, since the posterior 

 extremity of the maxillary extends to a vertical line drawn somewhat behind the posterior rim 

 of the orbit. The lower jaw is the longest, and, as already observed, the gape of the mouth is 

 directed obliquely upwards as in Uranoscopus . The teeth, at the symphysis of the lower jaw, 

 are more slender and smaller than on the branches of that bone (dentary). The smallest teeth 

 are those observed upon the premaxillaries, which extend almost to the entire length of these 

 bones. The palatine teeth are a little larger posteriorly than anteriorly ; the most conspicuous 

 ones are observed upon the vomer. The surface of the tongue is smooth. The side of the head 

 exhibits but one single spine inserted upon the opercle. It is quite acerated and conspicuous 

 though oftentimes covered by a thick skin. The branchiostegal apparatus is very much 

 developed ; the branchial apertures are wide, though separated beneath by a broad isthmus. 

 These apertures extend to the inferior surface of the head in advance and beneath the inferior 

 edge of the base of the pectoral fins, but not as far as the insertion of the ventrals. The 

 branchiostegal rays are well developed, six on either side. 



The first dorsal fin consists of two small spines situated somewhat in advance of the anterior 

 margin of the second dorsal, and oftentimes so inconspicuous as not to attract the attention of 

 the observer. The second dorsal is quite long, extending to almost the entire dorsal line ; it 

 increases slightly in height backwards and terminates near the insertion of the caudal, with 

 which it however does not unite, though the tips of the posterior rays overlap the base of the 

 last mentioned fin. The rays are very much subdivided ; the interradial membrane being quite 

 tough and strong. The origin of the anal is situated opposite the fifth or sixth ray of the 

 second dorsal and extends a little further back, though not united with the caudal. In structure 

 and shape it is similar to the second dorsal, the latter, mayhap, being somewhat higher than 

 the anal is deep. The interradial membrane appears also more thickish and tough, and the 

 extremity of each ray is expanded and projects beyond the membrane proper. The caudal is 

 comparatively quite a small fin ; it enters about nine times and a half in the total length. Its 

 posterior margin is rounded off. The pectorals are well developed, spear-shaped in general 

 appearance, the middle rays being the longest. Their base is very thick and convex ; the rays 

 are very much bifurcated. Their extremity projects considerably beyond the vent and the 

 anterior margin of the anal. The vent itself is situated close to the latter fin. The ventrals 

 are inserted under the throat in advance of the inferior edge of the branchial apertures. The 

 anterior ray is a rudimentary spine buried in the thickness of the skin which surrounds the 

 second ray, which is articulated only, whilst the following two and last are subdivided. Their 

 extremity hardly reaches the base of the pectorals. 



Br. VI : VI ; D II, 35 or 37 ; A 34 ; C 3, 1, 5, 5, 1, 2 ; V 1, 3 ; P 18 or 20. 



The head and body are scaleless. Minute cutaneous appendages may be observed upon the 



periphery of the maxillar bones, behind the premaxillaries, and also upon the inferior 



peripheric edge of the lower jaw, partly covered by the lips. There are several series of pores 



beginning upon the head and extending along the body. We observe one series, right and 



