379 



forms of other parts of the animal kingdom. As for the Herpeto- 

 logy in general, it is truly a debateable ground between PalsBOtro- 

 pioa] and Indian Ainphibio-fauna : but as for the (Jphidii, it be- 

 longs entirely to the Indian region; for the present, at Least, ire do 



not know one Japanese snake found also in the l'ahearctic region, or 

 even only belonging to one of its peculiar generic forms. 



II. .Ethiopian or Western Palaotropicai Region. 



Characteristic forms. — Hortulia, Sanzinia, Pelophilue, Caearea, 

 Calabaria. Ilomalosoma, Psammopkylax, Heteronotue, Prowmna, 

 Meizodon, Psammophie, Daeypeltie, Bucephalus, Hapsidopkrye, 

 Langaha, Simocephalus, Lanipropftis, Alopeeion, Lycophtdion, M<- 

 toporhina, Boodon, Holuropholis, Naja hqje, Cyrtophis, Elapel 

 hygice, Dendraspie, Causus, Sepedon, Atractaspis, Cfot/io. 



Forms common with other regions. — Philodryae, Ckryeopeiea, 

 Ahcetulla, Dryophis, Leptodeira, Dipsas, Dipsadoboa. 



. We now enter a tropical region, and immediately find forms of 

 gigantic magnitude, variety, and vivacity of coloration, and a great 

 multiplication of the number of generic forms and of species, al- 

 though only the southern part of this truly continental region has 

 been examined in a satisfactory manner ; it is not mam years since 

 the borders of Western and of part of Eastern Africa were searched 

 through ; and the great enrichment of zoological knowledge, produced 

 by tins first progress, promises the most extensive results to those 

 daring attempts to cross a continent which, instead of being a con- 

 tinuous burning desert, contains a new world of vegetable and animal 

 life. An enumeration of the reptiles of Western Africa, by Dr. Graj 

 (see ante, page 155 et -seq.), shows how greatly our knowledge of 

 the Herpetologv of that country has been enlarged in the lapse of 

 a few years. Thus I hope that the ratio here given of the geogra- 

 phical area and distribution of the Ophidians will only be a proof 

 of the distance between our present knowledge and that of the coming 

 decennium. Taking the area of this region at 12,000,000 square 

 miles, and the number of species of Snakes contained therein at 

 80, we have on the average a single species to each 150,000 square 

 miles, or 2^ species to the same area for which we found only one in 

 the paleearctic region. 



The number of Colubrina is again predominant, but is to that 

 of the Boina only as 8:1, and to that of the Viperina a< 11 : I •. the 

 proportional number of the Boina therefore is enlarged, that of the 

 Viperina diminished. We must observe, first, ns a peculiarity of 

 this region, that at present there is not one Bpecies known of the 

 genus Tropidonotus. Schlegel believed he found its represent at ive 

 in Daeypeltis scaber\ but a snake living on trees, devouring eggs of 

 birds, the shells of which it breaks by gular teeth, with irregular ar- 

 rangement of the lateral scales, i- s form quite peculiar in itself, and 

 quite peculiar to this region. Mighh interesting is tto fact, thai 

 more than one-third of the genera live on trees; which ratio is 

 never met with in anv of the other regions : there we find a member 



