422 TEIIDE, 
millim. millim. 
Total length (extremity Width of head ........ 4 
of tail lost)........ 122 Fromendof snoutto vent 64 
Had, 2s ieee ack awiess 6  Forelimb ..........+. 27 
Nauta, Peruvian Amazons. 
30. HETERODACTYLUS. 
Heterodactylus, Spix, Spec. Nov. Lacert. Bras. p. 25; Dum. §& Bibr. 
v. p. 444; Gray, Cat, Lis, p. 59, 
Chirocolus, Wagler, Syst. Amph. p. 157; Wiegm. Herp. Mex. p. 10. 
Tongue moderately elongate, arrow-headed, Lateral teeth bi- 
cuspid. Head with large regular shields; a frontonasal separating 
the nasals; prefrontals and frontoparietals absent; nostril pierced 
in the suture between the nasal and the first labial. Eyelids deve- 
loped, lower with a transparent disk. No ear-opening. Limbs 
short, with well developed digits; the inner finger rudimentary, 
tubercular, clawless. Dorsal and lateral scales equal, hexagonal- 
lanceolate, keeled, imbricate, forming transverse series; ventrals 
large, subquadrangular, rounded and overlapping posteriorly, smooth, 
arranged in regular longitudinal and transverse series, No collar 
fold. Tail cylindrical. Males with, females without, femoral 
pores. 
Brazil. 
1. Heterodactylus imbricatus. 
Heterodactylus imbricatus, Gray, Cat. p. 76. 
Heterodactylus imbricatus, Sper, 1. c. pl. xxvii. fig. 1; Dum. & Bibr. 
v. p. 447; Reinh. & Liitk. Vidensk. Meddel, 1861, p. 217, pl. vi. 
fig. 11; Peters, Abh. Berl. Ac, 1862, p. 172; Bouleng. Proc. Zool. 
Soc, 1885, p. 1. 
Head short, snout broad, truncate; body much elongate. Fronto- 
nasal large, hexagonal, broader than long; frontal narrower, penta- 
gonal, a little longer than broad; a pair of hexagonal parietals, 
followed by two pairs of large transverse occipitals ; interparietal very 
small or absent, seldom in contact with the frontal; three supraoculars; 
a narrow loreal; a row of small infraorbitals ; temples shielded; six 
upper and four lower labials ; chin-shields, one anterior and two large 
pairs, the first pair and sometimes also a short portion of the second 
forming a suture; median gulars transversely enlarged. A row of 
six elongate pectoral shields. Dorsal scales very narrow, lanceolate, 
ending in a long sharp point; thirty-three or thirty-five scales 
round the middle of the body, ventrals included; thirty-two to 
thirty-five scales from occiput to base of tail. Ventrals longer than 
broad, in six or eight longitudinal and twenty-five or twenty-six 
transverse series. Five elongate preanals, outer very narrow. 
Limbs with smooth shields. Male with four femoral and one or 
two preanal pores on each side. Tail extremely long and thick, 
tapering gradually at the end, covered with annuli of scales similar 
to the dorsals. Yellowish brown above, sides darker; a more or less 
