FRESH-WATER FISHES OF SIAM, OR THAILAND 547 



under eye to posterior edge of opercle thickly covered with rounded 

 dark brown spots ; a narrow dark stripe extending forward from each 

 eye to the base of the upper lip, stripes of the two sides meeting to form 

 a curve at base of upper lip ; first dorsal with obscure darkish spots ; 

 second dorsal with 6 or 7 oblique rows of dark spots ; caudal fin with 

 dark spots forming irregular cross bars ; anal fin distally blackish, with 

 a colorless edge ; ventrals with rays distally blackish ; pectorals pale, 

 with dusky edge, the fleshy base with a cross row of round brown spots. 



Tyfe and paratypes. — The type (U.S.N.M. No. 119580) is a female, 

 5.2 cm. long, including the caudal fin, collected August 14, 1934, by 

 Layang Gaddi, on Doi Hua Mot in Huey Melao, a tributary of the 

 Mekok that flows into the Mekong north of Chiengrai in Northern 

 Thailand. From the same brook and one of its branches, the Huey 

 Len, the same collector, on 5 days in August 1934, took 56 specimens 

 ranging in length from 2 to 5.3 cm. Paratypes are U.S.N.M. Nos. 

 119581-119586. 



Other specimens. — Three specimens, 3.7 to 4.7 cm. long, from the 

 Menam Mao, a branch of the Menam I'ang, tributary of the Mekong, 

 were taken by Deignan on December 25. 1936. 



Remarks. — This species has been found farther inland than any 

 other Thailand goby. It is very common in the Huey Melao, a typical 

 mountain brooklet, and appears to reach a maximum length of less 

 than 6 cm. 



The degree of squamation in the predorsal region varies within 

 narrow limits, and the median scales may be six to nine, with the 

 scales on the sides extending a little farther forward than those on 

 the median line. 



In some specimens there is a tendency for the spots on the sides to 

 form into obscure bands, blotches, or saddles, and the spots on the base 

 of the pectoral fins may become diffused or combined into irregular 

 patches or form into a vertical line. In some male specimens there is 

 on the first membrane of the first dorsal a spot that by its size and 

 blackness, stands out a little more distinctly than the other spots on the 

 fin. 



Specimens from the Menam Mao are comparatively dark, with the 

 body cross bands, the spots on head, and those on pectoral base very 

 distinct, and the lips fuller and broader, but such characters as squa- 

 mation and fin rays agree with the less highly colored specimens from 

 the Doi Hua Mot region. 



CTENOGOBIUS CYLINDRICEPS Hora 



CtenogoMus cylindriceps Hoba, 1923a, p. 745, figs. 26-28 (Chilka Lake) ; 1924a, 

 p. 494 (Tale Sap). 



Described in 1923 from numerous specimens from both fresh and 

 salt waters of Chilka Lake, India, this species was found by Hora to be 



