DACTYLOPERUS. 279 



The ground color of the upper regions is light or yellowish-brown, 

 with a few black dots, spots, or streaks, irregularly disposed. A con- 

 spicuous streak may be traced from the nostril to the eye, and from 

 behind the eye, across the auricular aperture, to the shoulder, or else 

 to the insertion of the anterior limbs. The inferior regions are uni- 

 color, of a soiled white. 



LOG. The label having been lost in the unpacking, the fatherland 

 of this species is not known to any degree of certainty. The speci- 

 men preserved is supposed to have been collected at Rio de Janeiro, 

 Brazil, from the recollection of the naturalists of the Expedition. 



GENUS DACTYLOPERUS, FITZ. 



GEN. CHAR. Pupil circular or elliptical. Fingers and toes free, 

 dilated upon their whole length, with two series of diverging plates 

 beneath, divided by a groove. Thumbs wanting the last joint, and 

 clawless. Upper regions covered with small, nearly equal scales. 

 Femoral pores in the male. Tail depressed, provided beneath with 

 large scutellae. 



o 



s, FITZ. Syst. Kept. 1843, 103. 

 Peripia, GRAY, Catal. Lizz. Brit. Mus. 1845, 158. 



OBSERV. This genus is closely allied to Peropus, from which it 

 differs by the shape of the pupil, the unwebbed toes, and the presence 

 of large plates or scutellae under the tail. To Boltalia it bears strong 

 analogies, if not affinities, for, the thumb exhibits the rudiment of the 

 last joint, which is adherent to the surface of the expanded digit, in- 

 stead of being free and simply inserted upon it. The claw is not 

 developed: a mere acute point being perceived at the apex of the rudi- 

 mentary joint. A fact like this cannot fail to have a weight in the 

 mind of some herpetologists, against the establishment of genera upon 

 characters apparently so slight as those upon which Boltalia, Dactylo 

 perus, and Peropus are based. 



