Distribution of the Lacertilia. 81 



are characterized by a mingling of European and Ethiopian 

 forms, with, however, strong predominance of the latter — the 

 true Lacertce being outnumbered by such forms as Eremias, 

 Acanthodactylus, &c., and the families Agamidse, Amphis- 

 bsenidse, and Chamseleontidge being represented by a greater or 

 less number of species. The homogeneity of the desert-fauna 

 which extends from North-west Africa to Sind is striking ; 

 not only the genera remain nearly the same, but even some of 

 the species are identical throughout or but slightly modified. 



African forms, such as the Lacertoid genera Eremias and 

 Scapteira, penetrate into Central Asia and Mongolia ; the 

 genus Phrynocephalus, so characteristic of that district, is but 

 a slightly modified form of the African Agama. By the 

 abundance of these types, and by the absence of the genus 

 Lacerto* and the Anguidce, the interior of Asia differs strongly 

 from Europe, without showing any relationship to the Oriental 

 Region ; its character is essentially African. The Manchu- 

 rian Subregion shows a decided preponderance of Indian 

 forms, as is rendered especially apparent by the presence of 

 several species of the genera Oecko and Tachydromus^ which 

 are otherwise restricted to the eastern parts of the Oriental 

 Region, extending far into the Indian archipelago, but not 

 ranging west of Bengal. Japan, with the widely-distributed 

 genus Eumeces and the genera Oecko and Tachydromus^ is 

 without any affinity whatever to the Palsearctic Region — a fact 

 in accordance with the distribution of Ophidians, as shown 

 by Dr. Giinther t, but different from that of Batrachians. 

 The Manchurian Subregion is therefore to be included in the 

 Oriental Region. The northern limit of the Lacertilia in Asia 

 is still to be ascertained } in Europe they are known to occur 

 as far as Lapland [Lacerta vivipara and Anguis fragilis) . 



2. The Ethiopian Region. — The affinity between this and 

 the preceding region is so great, and the passage between the 

 two so gradual, that it is hardly possible to draw any satis- 

 factory boundary-line ; should such a boundary have to be 

 traced, the southern limit of the Sahara appears to be the 

 most natural. The south of the African continent exhibits by 

 far the most varied Lizard-fauna, no less than ten families 

 (viz. Geckonidse, Agamidse, Zonurid^, Varanidge, Amphis- 

 bsenidge, Lacertidse, Gerrhosauridse, Scincidge, Anelytropidse, 

 and Chamgeleontidse) being represented, the smaller of which 



* A single species, Lacerta vivipara, ranges far to the east in Northern 

 Asia, its presence being recorded in Amoorland ; how far L, agilis ex- 

 tends into Siberia is unknown at present ; no other Lacertce are known 

 to occur in Siberia. 



t Proc. Zool. Soc. 1858, p. 379. 



