CrTAP. XIX.] 
REPTILES. 
387 
lidae. The Australian lias 16, "belonging to three families only ; 
eleven being Elapidae, and four Pythonidae. The Neotropical has 
about 24, belonging to eight families ; ten are Colubridse, six 
Pythonidse, and the rest Dipsadidse, Scytalidse, Amblyceplialidse, 
Elapidae, and Crotalidae. 
We find then, that in the Ophidia, the regions adopted in this 
work are remarkably distinct ; and that, in the case of the Orien- 
tal and Ethiopian, the difference is strongly marked, a very large 
number of the genera being confined to each region. It is in - 
teresting to observe, that in many cases the affinity seems to be 
rather between the West Coast of Africa and the Oriental 
region, than between the East Coast and the plains of India ; 
thus the Homalopsidae — a highly characteristic Oriental family — 
occur on the West Coast of Africa only ; the Dryiophidee, which 
range over the whole Oriental region, only occur in Madagascar 
and West Africa in the Ethiopian ; the genus Dipsos is found over 
all the Oriental region and again in West Africa. A cause for this 
peculiarity has been suggested in our sketch of the past history 
of the Ethiopian region, VoL I. p. 288. In the Lycodontidfe, 
which are strictly confined to these two regions, the genera are 
all distinct, and the same is the case with the more widely dis- 
tributed Elapidae ; and although a few desert forms, such as 
Echis and the Erycidae, are common to Africa and the dry plains 
of India, this is evidently due to favourable climatic conditions, 
and cannot neutralise the striking differences in the great mass 
of the family and generic forms which inhabit the two regions. 
The union of Madagascar with the South-western part of the 
Oriental region under the appellation Lemuria, finds no support 
in the distribution of Ophidia ; which, however, strikingly accords 
with the views developed in the Third Part of this work, as to the 
great importance and high antiquity of the Euro-Asiatic conti- 
nent, as the chief land-centre from which the higher organisms 
have spread over the globe. 
Fossil Ophidia . — The oldest known remains of Ophidia occur 
in the Eocene formation in the Isle of Sheppey; others are found 
in the Miocene (Brown Coal) of Germany, and in some Tertiary 
beds in the United States. Most of these appear to have been 
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