15. PANXODACTTLUS. IG. AiaHKOSATJEA. 389 



strongly imbricate, strongly keeled ; tweuty-four to twenty-six scales 

 round the middle of the body, including veutrals ; thirty to thirty-four 

 scales from occiput to sacrum inclusively. Yentrals large, in four 

 large longitudinal series, passing gradually into the dorsal scales. 

 Two jjairs of laige prteanals, posterior largest. Limbs with large 

 smooth shields ; lower surface of arm and hinder side of thighs granu- 

 late ; digits slightly, but distinctly, toothed inferiorly. Four femoral 

 pores on each side in the males, one or two in the females. Tail, 

 when intact, extremely long, gradually tapering to a fine point ; 

 the scales similar to those of the body. Olive or brownish, above, 

 sides darker ; a light streak on each side, commencing above the 

 ear ; a more or less distinct dark vertebral line ; lower surfaces 

 whitish, more or less dotted with grey. 



millim. millim. 



Total length 151 From end of snout to 



Head 9 vent 39 



Width of head Fore limb 11 



From end of snout to fore Hind limb 16 



limb 15 Tail 112 



Southern Brazil, Uruguay, Buenos Ayres. 



a-c. d, 2 , & yg. Rio Grande do SlJ. Dr. v. Iheriug [C.l. 



d-y. 5 & yg. S. Lorenzo, Rio Grande do Dr. v. Ihering [O. J. 



Sul. 



h. 2. Brazil. 



i. 5 . Montevideo. 



k-l. 2 & hgr. Dept. of Soriano, Uruguay. R. Havers, Esq. [P.]. 



m-2\ 2 & }'?• Uruguay. 



16. ARTHROSAURA. 



Tongue moderately elongate, arrow-headed. Lateral teeth com- 

 pressed, bi- or tricuspid. Head with large regular shields ; fronto- 

 nasal separating the nasals ; prtefrontals and frontoparietals present; 

 nostril pierced in the middle of a single nasal. Eyelids developed, 

 lower with a transparent disk composed of several scales. Ear 

 exposed. Limbs well developed, pentadactyle. Dorsal and lateral 

 scales equal, hexagonal-lanceolate, keeled, imbricate, arranged in 

 regular transverse series ; ventral plates large, subquadrangular, 

 rounded and overlapping posteriorly, smooth, arranged in regular 

 longitudinal and transverse series. A collar fold. Tail cylindrical. 

 Female without femoral pores. 



Ecuador. 



This genus forms a connecting link between Prlonodactijlus and 

 Ueterodactijlas. 



1. Arthrosaura reticulata. 



Cercosaura (Pautodactyhis) reticulata, O'Shauyhn. Proc. Zool, Soc, 

 1881, p. 230, pi. xxii'. lig. I. 



Head depressed, snout short, obtuse ; body rather elongate. A 



