204 OYPEINIDJE. 



with the paired fins and the membrane between the dorsal rays yellow or orange, and 

 the anal and caudal vermilion-red or suffused with salmon-pink, the ends of the dorsal 

 and caudal rays sometimes blackish. The iris is silvery and the pupil nearly perfectly 

 round. 



The largest specimen brought home by Mr. Loat is from the Fayum and measures 

 460 millim., but the species attains, under favourable circumstances, to even a larger 

 size. Mr. Loat measured a specimen of 530 millim. at Arko, and Capt. Flower 

 obtained one measuring 650 millim. and weighing over 12 lbs. from a pond near 

 Cairo ; some Bynnies are stated by Geoffroy St. Hilaire to exceed a length of 

 660 millim. Fry measuring from 18 to 40 millim. have been examined by me; they 

 differ in the non-ossification of the anterior rays of the dorsal fin. 



As may be seen from the table of measurements and of numerical characters, the 

 large series of specimens at my command reveals a greater amplitude of variation than 

 could be deduced from the systematic descriptions that have hitherto appeared of this 

 and allied species of the genus Barb us. The formula of fin-rays and scales as given by 

 Valenciennes and by Gunther, 



D. IV 9 ; A. Ill 5 ; L. iat. 35 ; L. transv. |, 

 has to be modified to 



D. IV 8-10 ; A. Ill 5 ; L. Iat. 31-39 ; L. transv. g=g. 



The original definition, nevertheless, still holds good for the great majority of the 

 specimens, since, out of two hundred and ten specimens examined by me, only nineteen 

 have 8 branched rays to the dorsal and ten have 10, whilst 1\ series of scales above 

 the lateral line occurs only three times and 5^ series four times, only twice do I find 

 6 \ series of scales between the lateral line and the mid-ventral line. 



Dr. Gunther says : " Tipper and lower lip sometimes tvith a well-developed lobe, 

 nearly as long as the eye, sometimes without a trace of it." These remarks are intended 

 to apply to the specimens of the Petherick Collection, which are preserved in the 

 British Museum. In the largest of these, stated to be from the Lower Nile, both the 

 upper and lower lips are nearly as much produced as in a B. nedgia ; in none of 

 the specimens collected by Mr. Loat are the lips developed to such a degree. 

 Whether a median lobe be distinct or not, the lower lip is always continuous across 

 the chin. 



The large Fayum specimen mentioned above is remarkable in having a supernumerary 

 barbel on the left side of the lower jaw. 



The Bynni is one of the best known fishes of Egypt and has a wide distribution, 

 being known not only from the Nile proper and the White Nile, but also from Lake 

 Baringo, whence specimens were sent to the British Museum by Sir Harry Johnston. 



