228 Mr. Blyth's Commentary 



the bulk of Dr. Jerdon's volumes. To a very great extent^ and 

 indeed essentially, the sub-Himalayan fauna^ up to the zone of 

 ConifercE, is an extension westward of that of the Indo-Chinese 

 subregion, as contrasted with the fauna of India proper ; and the 

 same more eastern faunaj in its low-country forms, extends also 

 to the Bengal Sundarbans and along the tarai or marshy tract 

 at the foot of the northern hills. A very marked change becomes 

 apparent on quitting the alluvium of the lower Ganges in a 

 westerly direction, where sundry species common to the Indian 

 peninsula with Ceylon at once present themselves abundantly 

 which never stray into Lower Bengal, while not a few of the 

 more characteristic species of Lower Bengal and of the Indo- 

 Chinese countries disappear as suddenly and entirely. 



In the higher ranges of the sub-Himalayas the Indo-Chinese 

 and more tropical forms give way, for the most part, to those 

 characteristic of the temperate parts of Europe and Asia ; and 

 the FringillidiE, in particular, become very numerous in species, 

 which, southward of the Himalaya, are replaced by Plocei and 

 Estreldina, one species only {Carpodacus erythrinus, besides 

 Emberizirue) extending far into the plains as an ordinary winter 

 visitant. The connexion of the avifauna of the Himalaya with 

 that of the plains is indeed chiefly maintained by species which 

 resort to the hills to breed and return to pass the winter south- 

 ward, insessorial birds being chiefly here referred to. 



The proper Indian fauna, as distinct from the sub-Himalayan, 

 culminates in the hills of Southern India and especially of Cey- 

 lon ; but a few peculiar species are elsewhere scattered within 

 the area of that particular fauna, as notably the remarkable 

 Tree-creeper, Salpornis spilonotus (akin to the Australian form 

 Climacteris), in the jungles of Behar, and the Courser-like 

 wader, Rhinoptilus bitorquatus (with a sole African congener), in 

 Northern Coromandel. The great plains of Upper India are repi'o- 

 duced in the tableland of the Dukhun, where again are charac- 

 teristic species (common to both) which have not been observed 

 elsewhere ; such are Hirundo concolor, Pericrocotus erythropyyius, 

 and Malacocercus malcolmi. But though subordinate provinces 

 are more or less traceable, as indicated by Dr. Jerdon in his 

 Introduction (xxxix et seq.), the most prominent distinction is 



