Nucras. 



1. NUCRAS. 



Nucras, G-ray, Aun. N. H. i, 1838, p. 280; Lataste, Ann. Mus. 

 Genova (2), ii, 1885, p. 124, ; Bouleng. Cat. Liz. iii, p. 52 (1887), and 

 Ann. S. Afr. Mus. xiii, 1917, p. 195. 



Lacerta, part., Dum. & Bibr. Erp. Gen. v, p. 174 (1839) ; Bedriaga, 

 Abh. Senck. Ges. xiv, 1886, p. 24 



Nucras, part.. Gray, Cat. Liz. p. 33 (1845). 



Zootoca, part., Gray, op. cit., p. 27. 



Bettaia, Bedriaga, t.c, p. 435. 



Head-shields normal. Nostril well separated from 

 the labials, pierced between two or three nasals. Lower 

 eyelid scaly. Collar well-marked. Dorsal scales small ; 

 ventral shields feebly imbricate, smooth. Digits cylin- 

 drical or very feebly compressed, with smooth lamellae 

 inferiorly. Femoral pores. Tail long, cylindrical. 



Tropical and South Africa. 



When, nearly 30 years ago, the late Dr. E. Klebs submitted to me 

 the oldest known Lacertid (Oligocene) with the Jepidosis preserved 

 through imbedding in amber, a careful comparison with recent lizards 

 led me to refer it to the genus Nucras, although the essential 

 generic character of the position of the nostril could not be ascertained, 

 my conclusion being based on an examination of the digits and of 

 the scaling of the gulai; and pectoral regions, more similar to those 

 of Nucras tessellata than of any other lizard with which I was 

 acquainted.* Since then I have made a more thorough study of the 

 LacertidsB from the point of view of their probable evolution, and 

 independent, correlative reasons have confirmed my provisional 

 identification so far that, quite apart from any palaeontolgical 

 consideration, I am now inclined to regard Nucras as, on the whole, 

 the most primitive genus of the Lacertidee. At the time I examined 

 the lizard in amber the representatives of the genus were believed to be 

 confined to Africa no further north than the Zambesi basin, and my 

 suggested identification may, therefore, have seemed somewhat risky 

 from the standpoint of zoogeography. We must, however, bear in 



* Cf. E. Klebs, Sohrift. Phys.-oet. Ges. Konigsberg, li, 1910, p. 227. I have 

 since proposed to designate the lizard as Nucras succinea. 



