1905.] OJf MEXICAN AMPHIBIANS AND REPTILES. 191 



The Larks and Pipits were, on the whole, very scarce. An 

 extremely handsome Glossy Starling was a very conspicuous bird, 

 which seemed to like the neighbourhood of camps. The White- 

 necked Crow and the fine Razoi'-billed Raven were especially 

 common in the west ; and it was in the cattle country and on 

 the Ruchigga Mountains that the Tick-birds {Bupliaga) were 

 observed, although some were seen following large herds of 

 elands in Bukanga and Mpororo, and the rhinoceros in Karagwe. 



Perhaps the most noticeable feature in the bird-life was the 

 extraordinary number of Francolins of every species to be seen in 

 Bukanga. Every valley and almost every patch of dry grass 

 appeai-ed to contain a large number of these birds. In the 

 evenings, when the grass had been burnt in patches, numbers of 

 Francolins could be observed feeding in the ojjen like pheasants 

 outside a cover in September at home. It would have been easy 

 to have shot forty or fifty brace a- day if time and cartridges had 

 been available. 



2. The Distribution o£ Mexican Amphibians and Reptiles. 

 By Hans Oadow, F.R.S., F.Z.S. 



[Eeceived May 17, 1905.] 

 (Text-figm-es 29-32.) 



Contents. 

 Introduction, p. 191. 



List of Species collected by H. G., p. 193. 

 Physical Features of the Localities, p. 196. 

 Keview of the Distribution of Cascilia, p. 199. 



„ „ Urodela, p. 200. Summary, p. 204. 



„ „ Anura, p. 205. ,, p. 208. 



„ „ Crocodilia, p. 209. „ p. 209. 



„ „ Chelonia, p. 209. „ p. 210. 



,) „ Lacertilia, i). 211. „ p. 220. 



„ „ Ophidia, p. 222. „ p. 226. 



Distribution according- to Altitude, p. 227. 

 List of Species occurring in High Altitudes, p. 232. 

 General Conclusions : — Evolution of Middle America, p. 234. 

 Immigration and Spreading, p. 238. 

 Northern and Southern Immigrants, p. 241. 



IXTRODUCTION. 



These investigations are based upon a considerable material 

 which it is convenient to enumerate : — 



, 1 . The volume on Reptilia and Batrachia, by Dr. Giinther, of 

 the ' Biologia Oentrali- Americana,' with its thousands of references 

 to localities. 



2. Cope's posthumous work, ' The Crocodilia, Lizards, and 

 Snakes of North America,' Rep. U.S. National Museum for 1898. 



3. Boulenger's Catalogue, with the lists of ever-increasing 

 additions, of the Collection in the British Museum of ISTatural 

 History. 



4. Collections made by Dr. Meek during his ichthyological 



