126 MONACANTIIUS. 



NOTE X. 

 ON A SMALL MONACANTHUS 



Dr. C. M. L. POPTA, 



June 1900. 



Among fishes seut to the Leyden Museum by the late 

 Dr. Bleeker, I found a Monacanthus which I cannot bring to 

 one of the described species. It is a small specimen and it may 

 be young, it is however interesting on account of its beautiful 

 markings. When later on more or larger specimens will be 

 found and it is proved that it is not the young state of a form 

 already known, I propose to call it Monacanthus radiatus. 



The body is oval ; the height, measured along the vertical 

 line immediately before the second dorsal and the anal fin, 

 is contained 2 times in the length without caudal and 

 2.J times in the length with caudal ; the breadth is con- 

 tained 4 times in this height; the head is pointed and 

 contained 4 times in the length with the caudal, in the 

 posterior part higher than long, its upper profile is ante- 

 riorly concave, posteriorly convex; the diameter of the 

 eye is contained 2[ times in the length of the head; the 

 snout, to the anterior border of the eye, is contained 

 1 ? times in the length of the head ; the lower jaw is 

 rather produced ; the four median teeth in the outer series 

 of the upper jaw are pointed, longer than the lateral one 

 on each side, which is more rounded ; the teeth in the 

 lower jaw are oblique, with a point on the side directed 

 to the median, rounded on the other side, the median 

 ones are the longest, the lateral ones the shortest; the 

 gill-opening is very slightly oblique, just behind the ver- 

 tical line of the posterior border of the eye and just before 

 the vertical line of the base of the pectoral fin, infe- 

 riorly commencing a little under the horizontal line of the 



Notes froin tlie Leyden Mviseum, "Vol. XXII. 



