398 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



of Vinciguerra's description until 1929 the species seems to have been 

 lost sight of. At that time a specimen that was clearly referable to 

 this form was collected in a tributary of the Tapi River in Peninsular 

 Siam. In October 1932, five other specimens were obtained by the 

 Siamese Forest Department for the Siamese Bureau of Fisheries in 

 the Meyuam, at Mesarieng in Northern Thailand, and in January 1933 

 the writer took another specimen in the same place. 



More recently this species has been found to be common in the 

 Meping at Chiengmai. Fowler recorded a series of 159 specimens 

 taken between December 1932 and March 1933 ; and Diegnan took a 

 dozen specimens in April 1935. The latter have the entire upper sur- 

 face of the brown body and head thickly covered with pale rounded 

 or elongate flattened tubercles, and all show, as their most conspicuous 

 marking, a whitish saddle-shaped spot corresponding with the inter- 

 spinous dorsal plate (as described and figured for G. dorsalis by Vinci- 

 guerra) and a similar spot involving the occipital process and the 

 skin on either side. The largest of three males was 9.3 cm. long, the 

 average being 9.1 cm. ; of 7 females the largest was 8.1 cm. long, the 

 smallest 7.4, and the average 7.7 ; 2 females of 7.4 cm. had the abdomen 

 distended with well-developed eggs. A fish of this lot that was partly 

 digested and had evidently been in the stomach of another fish was 

 a female, 9.1 cm. long to base of caudal fin, fully distended with ripe 

 eggs which were 0.8 mm. in longest diameter and 0.6 mm. in shortest 

 diameter. The midline of the back posterior to the dorsal fin showed 

 a continuous series of exposed bony scutes. Dr. Hora, who kindly 

 examined the specimen and identified it as G. platypogonoides^ wrote : 



The dorsal scutes are the ends of neural spines which, due to partial macer- 

 ation of the tissue, project beyond the skin. Such artifacts led some of the 

 earlier ichthyologists to distingush genera, and among siluroids we have an ex- 

 actly similar case in the genera Ailia Gray and Acanthonotus Gray. For the 

 latter it was stated by the author that "a series of small spines" is situated 

 before the adipose dorsal. 



Vinciguerra compared his fish with various Indian species but not 

 with forms from the Indo-Australian Archipelago. Had he done so, 

 he would undoubtedly have observed the resemblance between G. 

 doi'salis and G. platypogonoides. In body proportions, fin rays, size 

 of fins, length of barbels, and other characters, the two forms agree 

 closely, and even in coloration there is little disagreement. With the 

 information now available, dorsalis is to be regarded as a synonym 

 of platypogonoides. 



It seems probable that the single specimen of Glyptothorax col- 

 lected by Dr. Malcolm Smith from a stream in the hills of Nakon 

 Sritamarat, Peninsular Thailand, and described by Dr. Hora (1923b) 

 under the name G. siamensis^ may likewise prove to be the present 

 species, formerly credited with being peculiar to Sumatra. A com- 



