42 silurid^:. 



the total length (without caudal), the length of the head nearly five 

 times. Nape of the neck not elevated. The maxillary barbels extend 

 to the second third of the anal ; mandibulary barbels minute. Cleft 

 of the mouth less than twice as broad as long. Pectoral fin not longer 

 than the head, with the spine scarcely denticulated. Dorsal fin a 

 little in advance of the ventrals. 

 Sumatra ? 



a. Type of the species : not good state. From Dr. P. v. Bleeker's 

 Collection. 



Bleeker has overlooked the mandibulary barbels in this species ; 

 tUey are minute. 



8. Cryptopterus lais. 



Silurus lais, Bleek. Nat. Tydschr. Nederl. Ind. ii. p. 428. 

 Krvptopterichthys lais, Meek. Prodr. Silur. p. 291, and Atl. Ichth. Silur. 

 p. 88. tab. 90. fig. 2. 



B. 8-9. D. 1-4. A. 58-66. P. 1/10-11. 



The height of the body is contained three times and three-fourths 

 or four times in the total length (without caudal), the length of the 

 head five times and a half to six times and a third. Nape of the neck 

 slightly concave. The maxillary barbels extend to, or nearly to, the 

 middle of the anal ; mandible apparently without barbels. Pectoral 

 fin much longer, pectoral spine shorter than the head; the latter 

 without denticulations. Dorsal above the ventrals. 



Borneo. 



a. Three inches long : not good state. From Dr. P. v. Bleeker's Col- 

 lection. 



C. Maxillary barbels short ; mandibulary barbels short, if present. 

 a. Head and snout short. 



9. Cryptopterus micropus. 



Silurus cryptopterus, Bleek. Nat. Tydschr. Nederl. Ind. i. p. 270. 

 Krvptopterus micropus, Bleek. Prodr. Silur. p. 84, and Atl. Ichth. Silur. 

 p. 86. tab. 89. fig. 3. 



B. 10-11. D. 0-2. A. 64-72. P. 1/13-15. V. 6-7. 



The length of the head is contained five times and a third to six 

 times and a fourth in the total (without caudal) ; the diameter of 

 the eye is one-third of the length of the head ; the lower jaw is the 

 shorter ; the cleft of the mouth is not quite twice as broad as long. 

 The maxillary barbels extend scarcely to the base of the pectoral ; 

 those of the mandibles are minute, scarcely visible. Pectoral fin 

 much longer than, pectoral spine as long as, or even longer than, the 

 head ; the latter scarcely denticulated. 



Sumatra and Borneo. 

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



b-h. Adult, half-grown, and young. Siam. Purchased of Mr. Jamrach. 

 i. Adult. Purchased of Mr. Frank. 



