390 Transactions. 



close to the bottom, heading up-stream. The ventral fins are large and 

 muscular, and may, indeed, be used for clasping stones ; while the tail, as 

 would naturally be expected in a fish living in rushing waters, is large and 

 powerful. The pectoral, also, has its longest rays in the lower half of the 

 fin. 



As above noted, Haast bestowed the name Cheimarrichthys in 1874. 

 In the same year Sauvage used the form Chimarrichthys for an Indian 

 Siluroid. This latter being of actual later date was superseded by Euchilo- 

 glanis, given by Regan in 1907. 



Neither the original description nor figure of C. fosteri appear to be quite 

 accurate : for example, the number of dorsal spines is stated to be 3, whereas 

 4, the correct number, are shown in the illustration ; the pectoral and 

 ventral are shown too far apart ; and the very peculiar colour-markings 

 are not hinted at, either in the description or figure. Under these circum- 

 stances, the following description and accompanying figure will be useful. 



Haast placed the genus Cheimarrichthys under the Trachinidce as then 

 constituted, but recently Boulenger* has studied the somewhat hetero- 

 geneous assemblage, and has so narrowed the family down that it includes 

 the single genus Trachinus only, which dift'ers fundamentally, however, 

 only by having the second suborbital produced in an internal lamina sup- 

 porting the globe of the eye. Cheimarrichthys does not possess this sub- 

 ocular lamina, and Boulenger associates it with Leposcopus and other 

 genera to form the family Leptoscopidce. To the osteological characters 

 already ascertained I may mention that the vertebrae number 33. 



Cheimarrichthys. 



Family Leptoscopidce. Scapular foramen wholly in the hypercoracoid ; 

 pterygials well developed, separate ; no subocular lamina ; ventrals jugular; 

 head and body anteriorly depressed ; tail compressed ; mouth moderate, 

 slightly oblique ; the upper jaw overhanging the lower ; teeth villiform, in 

 the jaws and on the vomer ; eyes supero-lateral ; dorsal fin subcontinuous, 

 the spinous portion short and low ; head naked ; body with ctenoid scales, 

 lateral line nearly straight ; gill-membranes free from the isthmus. 



Cheimarrichthys fosteri, Haast. 

 Trans. N.Z. Inst., vi, 1874, p. 103, pi. xviii. 



B. VII ; D. IV, 20 ; A. 14 ; V. I, 5 : P. 15 ; C.l2 + x; L. lat. 50 ; 

 L. tr. circ. 10-10. 



Length of head, 3-7 ; height of body, 4-3 (or rather less than the width of 

 the head) ; length of caudal, 4-5 in the total : diameter of eye, 5 ; length 

 of snout, 2-2 ; interorbital space, 6-5 in the head. 



The head is very broad and markedly depressed, the lower surface flat ; 

 the interorbital space is flat, and in profile forms an obtuse angle with the 

 snout ; the eyes cut the profile, and are directed as much upwards as 

 laterally ; the nostrils, two on each side, are large round openings with 

 fleshy rims, the rim being highest behind on the anterior pore, and highest 

 in front on the posterior one ; they lie close together, a short distance in 

 front of the eye, and each pair is separated from its fellow by a space equal 

 to the interorbital ; the mouth is moderate, non-protractile, with large 



* Boulenger, Ann. Mag. Nat. Hist. (7), \aii, 1901, p. 261. 



