420 TEIIDE. 
29. OPHIOGNOMON. 
Ophiognomon, Cope, Proc. Ac. Philad. 1868, p. 100. 
Hapalolepis, Peters, Mon. Berl. Ac. 1871, p. 399. 
Propus, Cope, Proc, Ac. Philad, 1874, p. 70. 
Tongue moderately elongate, arrow-headed. Teeth conical. Head 
with large regular shields; frontonasal, prefrontals, and fronto- 
parietals absent; nasals forming a suture ; nostril pierced in the 
suture between the nasal and tho first labial. Eyes minute, eyelids 
developed. No ear-opening. Body and tail elongate, vermiform ; 
limbs rudimentary, the anterior with tubercle-like indications of 
digits, the posterior reduced to a minute tubercle or altogether 
absent. Scales smooth, forming regular annuli, and also longitudinal 
series on the belly ; the dorsals narrow, hexagonal or quadrangular, 
juxtaposed or slightly overlapping; the ventrals broader, quadran- 
gular, juxtaposed. A more or less distinct lateral fold. No collar 
fold. Males with preanal pores. 
Upper Amazons. 
Synopsis of the Species. 
Hind limb present, half as long as preanal 
plates ; 20 scales round the body ...... 1. trisanale, p. 420. 
Hind limb present, reduced to a minute 
tubercle; 26 to 28 scales round the 
OEY 2s sini aad ew wos eke end Seana Aidala Ae 2. abendrothit, p. 421. 
Hind limb absent ...... 0... 0c eee eee 3. vermiforme, p. 421. 
1. Ophiognomon trisanale. 
Ophiognomon trisanale, Cope, J. c. 
Fore limb as long as three anterior labials, with three terminal 
tubercles ; hind limb styliform, minute, half as long as anal plates. 
Snout obtuse, slightly projecting. Frontal large, hexagonal, posterior 
angle prolonged; parietals larger, obliquely hexagonal, truncate 
behind ; no interparietal; two supraoculars; a square loreal; two 
very small infraorbitals ; temporals three, anterior large ; four upper 
labials, posterior largest ; lower labials three; mental narrow; chin- 
shields, one anterior and three pairs, anterior pair extensively in 
contact, the posterior smaller and separated from temporals by four 
narrow plates, and from each other by four plates, the median pair 
of which are larger and join the anterior pair of chin-shields. A 
groove surrounds the throat behind the jaws, which is succeeded by 
five annuli of equal ovate scales ; these are followed by a cross series 
of six more elongate, which precede a pair of large sternal plates. 
Dorsal scales hexagonal ; twenty scales round the body and thirty- 
seven transverse rows between axilla and groin. Three elongate 
parallel anal plates. Caudal scales angulate, like dorsals. Below 
brown ; sides with a brown blackish band, which is bounded above 
