44 SILURIDJE. 



than the head, with the spine slender and slightly denticulated. The 

 length of the lower caudal lobe is three-quarters of that of the head. 

 Borneo and Sumatra. 



a. From Dr. P. v. Bleeker's Collection. 



13. Cryptopterus bleekeri. 



Micronema bleekeri, Boconrt. 



B. 14. A. 77-78. P. 1/14. V. 9. 



Maxillary barbels short, extending to the anterior margin or to 

 the middle of the eye ; mandibulary barbels minute, scarcely visible. 

 The height of the body is contained six times in the total length, the 

 length of the head four times and two-thirds ; the depth of the head 

 is equal to one-half of its length ; the diameter of the eye is one- 

 fifth or one-sixth of the length of the head. Lower jaw prominent. 

 Pectorals shorter than the head, with the spine slender and obtusely 

 denticulated. Caudal fin rather short, its length being equal to the 

 distance of the pupil from the opercular margin. 



Siam. 



a. Young. From Dr. v. Bleeker's Collection. 



b. Ten inches long. Siam. Purchased of Mr. Jamrach. 



14. Cryptopterus leptonema. 



Silurus leptonema, Bleek. Nat. Tydschr. Nederl. Lid. iii. p. 584. 

 Phalacronotus leptonema, Bleek. Prodr. Silur. p. 304, and All. Ichth. 

 Silur. p. 92. tab. 94. fig. 2. 



B. 16. A. 75. P. 1/14. V. 9. 



One pair of barbels only, extending to the eye. The height of the 

 body is contained five times and two-thirds in the total length (with- 

 out caudal), the length of tbe head five times ; the depth of the head 

 is more than one-half of its length ; the diameter of the eye is one- 

 fifth of the length of the head. Lower jaw prominent. Pectoral 

 rather shorter than the head, with the spine slightly denticulated ; 

 the length of one of the caudal lobes is three-quarters of that of 

 the head. 



Sumatra. 



II. Anal united with caudal. 



15. Cryptopterus gangeticus. 



Pterocryptis gangetica, Peters, Monatsber. Berl. Acad. 1861, p. 712. 

 B. 12. D. 2. A. 75. P. 1/12. V. 10. 



The height of the body is contained nine times and a half in the total 

 length (with the caudal), the length of the head nearly seven times. 

 The maxillary barbels do not quite extend to the pectorals, those of 

 the mandible reach to the margin of the gill-membrane. (Pet.) 



Ganges. 



