264 MR. C. TATE REGAN ON THE 
clavicles; abdomen covered by 5 longitudinal series of plates. D. 17; origin of dorsal 
above that of ventrals, the length of its base equal to its distance from supraoccipital. 
Adipose fin present. A.1 6. Pectoral spine extending to middle of ventral. Caudal 
emarginate. Caudal peduncle slightly compressed, 3} times as long as deep. 
Olivaceous ; caudal with brownish spots or bars. 
Total length 70 mm. 
‘lwo specimens: Upper Amazon. 
2. HYPopTOPOMA CARINATUM. 
Hypoptopoma carinatum Steind. Denkschr. Ak. Wien, xli. 1879, p. 49, pl. iv. fig. 3. 
Oxyropsis wrightiana Eigenm. & Eigenm. Proc. Cal. Ac. (2) il. 1889, p. 39, and Occ. Pap. Cal. 
Ac. i. 1890, p. 387. 
Depth of body 7} times in the total length, length of head 3} times. Diameter of 
eye 54 times in the length of head, interorbital width 2-25 times. Occipital region 
evenly convex, without median ridge. Scutes spinulose, 25 in a longitudinal series, 
those of the middle lateral series with a median keel. Lower surface of head with a 
naked area in front of clavicles; abdomen covered by 3 longitudinal series of plates. 
D. 17; origin of dorsal above that of ventrals, the length of its base a little more than 
its distance from supraoccipital. No adipose fin. A.1 5. Pectoral spine extending 
’ 
to middle of ventral. Caudal emarginate. Caudal peduncle depressed, broader than 
deep, its depth about 7 times in its length. Olivaceous, lower lobe of caudal 
blackish. 
Total length 41 mm. 
One specimen (type of Oxyropsis wrightiana): Upper Amazon. 
3. HyrorropoMa GUENTHERI. (Plate XV. fig. 2.) 
Hypoptopoma guentheri Bouleng. Proc. Zool. Soc. 1895, p. 526. 
Depth of body 53-5% times in the total length, length of head nearly 3 times. 
Diameter of eye 5-6 times in the length of head, interorbital width 1{ times. 
Occipital region evenly convex, without median ridge. Scutes spinulose, not carinate, 
22 in a longitudinal series. Lower surface of head with a transverse series of 4 small 
plates in front of the clavicles; abdomen covered by 2 longitudinal series of plates, 
the third series represented by a single anterior median plate. D.17; origin of dorsal 
above that of ventrals, the length of its base equal to its distance from the supra- 
occipital. No adipose fin. A.1I5,. Pectoral spine extending to posterior extremity 
of ventral. Caudal emarginate. Caudal peduncle slightly compressed, 33-3} times as 
Jong as deep. Dorsal and caudal with dark spots or bands. 
Total length 65 mm. 
Seven specimens from Descalvados, Matto Grosso, Paraguay System. 
a 
