3. CENTROPYX. 341 
above and beneath by a broad black band or a series of black spots ; 
a second, more or less distinct, light lateral line, beginning from the 
ear; lower surfaces greenish white. 
millim, millim. 
Total length ...... 344 Fore limb........ 37 
Cad nr ary od aces 24 Hind limb........ 68 
Width of head .... 15 Pall Sra vials gus sus 245 
Bodys.2, ecsaucee es 75 
Guianas, Brazil. 
a 9. Demerara. 
b&. . British Guiana. 
od. 2. S. America. T, Bell Esq. [P.]. 
e-h, i,k. Q & her. S. America. 
The fact that all the specimens examined by various authors as 
well as by myself are females, makes it possible that C. intermedius 
is the female of C. striatus, as already suggested by Troschel. How- 
ever, this is by no means certain, and the characters which separate 
the two forms are not of a kind known to vary according to sexes in 
other genera of lizards. 
3. Centropyx calcaratus. 
Kentropyx calcaratus, Sper, Spec. nov. Lacert. Bras. p. 21, pl. xxii. 
fig. 2. 
Lacerta striata (non Daud.), Wied, Abbild. 
Trachygaster calcaratus, Wagl. Syst. Amph. p. 164. 
Teius (Centropyx) calcaratus, Gray, Grif. A. K. ix. Syn. p. 31. 
Centropyx vittatus, Wiegm. Herp. Mex. p. 26. 
calcaratus, Dum. §& Bibr. v. p. 149; Cope, Proc. Ac. Philad. 
1861, p. 495 ; Peters, Mon. Berl. Ac. 1869, p. 64, and 1877, p. 412. 
Interorbital and occipital region concave in full-grown specimens, 
bordered by a prominent ridge. Gular scales small, subhexagonal, 
keeled, juxtaposed or slightly imbricate, slightly enlarged on the 
middle of the throat ; the edge of the collar not, or but very slightly, 
denticulated ; the last row of mesoptychial plates composed of fifteen 
or sixteen plates, sometimes even separated from the fold by granules. 
Median dorsal scales only a little enlarged, subhexagonal, juxtaposed, 
keeled ; scales on the flanks very small, almost granular. Median 
temporal scales minute. Ventral plates in fourteen or sixteen longi- 
tudinal and thirty-three to thirty-five transverse series. Preeanal 
scales smooth in the males, strongly keeled in the females ; the former 
with two large preanal spines on each side. Inferior femoral scales 
very small, those of the lower series hardly as large as the median 
gulars. Femoral pores seventeen to nineteen. Olive above; a 
light line on each side of the body, commencing from the eye, 
bordered inferiorly, and sometimes also superiorly, by a row of black 
spots, which may be confluent into a band; females with a broad 
median yellowish band on the head, which is generally lost on the 
