LABEIME. 85 



Family LABIUM:. 



XIPHOCHILUS, Bleek. 



293. Xiphochilus robustus. Hate XII. fig. 3. [667.] 

 Xiphochilus robustus, Giinth. Fish. iv. p. 98. 



This species is sufficiently described in Giinther's Catalogue of Fishes. In the specimen 

 from Zanzibar the formula of the dorsal fin is ^, and in that from Mauritius ^ ; in the 

 latter specimen the twelfth spine is turning into a ray, the lower half being spinous 

 and the upper half articulated, but not branched. 



Colour in life. — Upper part fawn, lower white. A broad whitish oblique band 

 ascending from the root of the pectoral to the back of the tail behind the termination 

 of the dorsal ; on the upper margin of this band the colour of the body is darker ; each 

 scale, except on the band and lower part of the body, has an indistinct pale-blue vertical 

 line. Lips cobalt-blue; a similarly coloured line through the centre of the orbit, 

 another along its base, and a third below it ; a blue line on the operculum, parallel to the 

 posterior limb of the prseoperculum ; opercular membrane blue. Five or six longitudinal 

 blue lines on the tail. Dorsal yellowish, with blue margin and base and a band of blue 

 marks along the middle. Anal yellowish, with a series of blue spots along base, a 

 bluish margin, and a very distinct yellow intramarginal band. Caudal with blue lines 

 along the rays ; ventrals and pectorals pale fawn. 



Length 11 inches. 



Zanzibar. Mauritius. 



294. Xiphochilus gymnogenys, sp. n. Plato XII. fig. 4. [198.] 



D. ^. A. J. L. lat. 29. L. transv. 21/11. 



Diagnosis. — The greater part of cheek and of sub- and interoperculum naked ; 

 but there is a patch of small scales, as large as the eye, below its posterior edge. Hind 

 part of gill-cover produced into a long flexible flap, fitting above the axil of the pectoral. 

 Interoperculum extremely broad, flexible, partly covering its fellow below the throat. 



Description. — Xiphochilus robustus, and still more X. gymnogenys, form a transition 

 between this genus and Chazrops, the pharyngeal bones of X. gymnogenys bearing ;i 

 much greater resemblance to that genus than to X. typus. 



The height of the body is contained nearly four times, and the length of the head 

 nearly three times and two-thirds in the total length. The maxillary does not reach to 



the anterior margin of the orbit. Prseorbital much higher than the orbit. Cheek 

 naked, with the exception of a patch of scales below the posterior margin of the eye. 

 The posterior margin of the praeoperculum very slightly denticulated ; the operculum, 



