10. ORESTIAS. 309 



a Female 8 inches long. From Mr. Pentland's Collection. 



b-c/, e-g. Half-grown and young. From Mr. Pentland's Collection. 



2. Orestias pentlandii. 



D. 13-15. A. 16-17. L. lat. 60. 

 Body rather elongate than stout; head three-fifths as high as 

 long, Its length being one-fourth of the total (without caudal). Eye 

 rather small, nearly one-sixth of the length of the head in lar-e 

 examples, and one-fourth in younger ones. Snout of moderate 

 length, longer than the eye, truncate, the lower jaw being vertically 

 directed upwards; prseorbital subquadrangular, rather longer than 

 high. The scales on the cheek leave a broad ring round the orbit 

 and a large space behind the maxillary uncovered. Adult specimens 

 have the scales on the head and the upper part of the trunk but 

 slightly granular, and only those of a series running above the oner- 

 ciilum are conspicuously enlarged. The length of the posterior limb 

 ot the pra3operculum is more than two-thirds of that of the lower 

 Pectoral terminating at a great distance from the vent. The distance 

 between the dorsal and caudal fins is more than the length of the base 

 ot the lormer. 

 Lake Titicaca. 



a-h Females, 7| inches long. From Mr. Pentland's Collection 

 c. feeveral young and half-grown specimens. From Mr. Pentland's 

 CoUection. 



3. Orestias jussiei. 



C«r. <5- Ta/. xvui. p. 235, pi. 535, cop. by Casteln. Anim. Amir. Sud, 



D. 14. A. 15. L. lat. 33. 



Body rather stout, neck elevated and much arched; head nearly 

 three-fourths as high as long, its length being contained thrice and 

 a third m the total (without caudal) ; anterior part of the head com- 

 pressed : snout as long as the eye, truncate, the lower iaw bein- 

 verticaUy directed upwards. Eye one-fourth of the length of the 

 head m a specimen 3| inches long. Praeorbital irregular in shape 

 deeper than long. Cheeks entirely covered with hard, horny scales •' 

 the scales on the trunk and on the head are enlarged, verv thick and 

 horny but smooth. The length of the posterior limb of the prs- 

 opercu um nearly equals that of the lower. Pectoral terminating at ' 

 some distance from the vent. The distance between dorsal and 

 caudal fins equals the length of the base of the former. 



Lake Titicaca. 



a. Three and a half inches long. From Mr. Pentland's CoUection. 



