On a new Characinid Fi.<hfrom Mexico. 497 



1 1 ylambatcs vermicuhilus. 



Vomerine tectli in two sni:ill groups on a level with the 

 posterior herder of the choana\ Head hroiider than ioiip, 

 .stron;::ly depressed ; snout roiindo 1, as h)nf^as the eye; iiiter- 

 orhital space hroadt-r than the upper eyelid ; tym|)anum very 

 distinct, two-thirds the diameter of the eye. Finf^ers mode- 

 rate, with a mere rudiment of web; toes half-webbed ; disks 

 well developed; suharticular tubercles moderate ; inner meta- 

 tarsal tub(M-Lde rafhiM- small, oval, feebly prominent. The 

 tibio-tarsal articulation reaches just in front of the eye. Skin 

 smooth above, ;^ranul.ir beneath. Green above, vermiculatod 

 with black; upper lip with black and white spots; flanks, 

 upper arm, and sides of thiLjh black with large white mar- 

 l»ling; fingers and toes barred black and white; lower parts 

 white, belly with a few brown spots. 



From snout to vent ijl mm. 



Amani. 



LX. — Description of a new Characinid Fish from Mexico. 

 By G. A. BoulenTtER, F.R.S. 



(Publidhod by permission of the Trustees of the British Museum.) 



Chirodon arnoldi. 



Depth of body 3 times in total length, length of head 

 4 times. Body very strongly compressed. JSnout shorter 

 than eye^ which is 2f times in length of head and equals 

 width of slightly convex interorbital region ; maxillary not 

 extending quite to below anterior border of eye ; lower jaw 

 scarcely j)r(>jecting. Dorsal II 9, originating just behind 

 base of ventrals, and at equal distance from end of snout and 

 from root of caudal; longest ray as long as head. Anal 

 111 19. Caudal deeply forked. 32 scales in a longitudinal 

 and 11 in a transverse series; lateral line reduced to 4 or 5 

 anterior scales. Yellowish above, finely speckled with black, 

 silvery white l)eneath ; a large round black spot on caudal 

 peduncle, extending on base of middle rays of caudal ; dorsal, 

 ventrals, and caudal tinged with orange. 



Total length 33 mm. 



This new tish, the type of which has been presented to the 

 British Museum, was received from .Mr. J. Paul Arnold, who 



