CHAP. XIX.] 
REPTILES. 
403 
General Remarks on the Distribution of the Lacertilia. 
The distribution of the Lacertilia is, in many particulars, 
strikingly opposed to that of the Ophidia. The Oriental, 
instead of being the richest is one of the poorest regions, both 
in the number of families and in the number of peculiar genera 
it contains ; while in both these respects the Neotropical is by 
far the richest. The distribution of the families is as follows 
The Nearctic region has 7 families, none of which are peculiar 
to it; but it has 3 peculiar genera — Ghirotes , Ophisaurus , and 
Phrynosoma. 
The Pakearctic region has 12 families, with two (Ophio- 
moridse and Trogonophidse, each consisting of a single species) 
peculiar ; while it has 6 peculiar or very characteristic genera, 
Trogonophis in North Africa, Psammodromus in South Europe, 
Hyalosaurus in North Africa, Scincus in North Africa and Arabia, 
Ophiomorus in East Europe and North Africa, and Phrynocephalus 
in Siberia, Tartary, and Afghanistan. We have here a striking- 
amount of diversity between the Nearctic and Palsearctic 
regions with hardly a single point of resemblance. 
The Ethiopian region has 13 families, only one of which (the 
Chamsesauridse, consisting of a single species) is altogether pecu- 
liar; but it possesses 21 peculiar or characteristic genera, 9 
belonging to the Zonuridae, 2 to the Sepidse, 7 to the Geckotidse, 
and 3 to the Again idae. 
The Oriental region has only 8 families, none of which are 
peculiar ; but there are 28 peculiar genera, 6 belonging to the 
Scinckke, 1 to the Acontiadse, 5 to the Geckotidse, and 16 to the 
Agamidse. Many lizards being sand and desert-haunters, it is not 
surprising that a number of forms are common to the border- 
lands of the Oriental and Ethiopian regions ; yet the Sepidse, so 
abundant in all Africa, do not range to the peninsula of India ; and 
the equally Ethiopian Zonuridse have only one Oriental species, 
found, not in the peninsula but in the Khasya Hills. The Acon- 
tiadse alone offer some analogy to the distribution of the Lemurs, 
being found in Africa, Madagascar, Ceylon, and the Moluccas. 
The Australian region has 11 families, 3 of which are pecu- 
d d 2 
