282 Herr E. Ilartert on the Caprimulgidse. 



remarks : — '' The ' Large Bengal Nightjar ' is very similar to 

 the ' Malay Nightjar/ and is liable to be confounded with it. 

 The two species, in fact, grade into each other with respect 

 to size, and had I more birds available for examination I 

 should probably be led to unite them/' If one compares a 

 real C. macrurus from Malacca, Sumatra, or Java with 

 specimens of C albonotatus from N.W. India, he is easily 

 convinced that they are two totally different species. But 

 comparing a series of several dozens of each from the above- 

 named localities he will make the remark that they vary 

 much in colour ; and on comparing a good series of birds from 

 Tenasserim, Burmah, and Assam he will see that in the latter 

 localities many intermediate phases occur, so that it is 

 impossible to draw an exact line between the two forms. Still 

 the extremes are very different, and therefore I am not pre- 

 pared to follow one of the two ways which are the only 

 possible ones, as Mr. Ilume thinks (' Stray Feathers,^ 1878, 

 ii. p. 257, note), and which also Mr. Oatcs seems to regard 

 as the only possible ones, i. e. either to unite them under 

 one name or to keep them up as two different species, but I 

 shall treat them as subspecifically distinct. If I were to unite 

 them under one specific name, no doubt many subsequent 

 writers would correct me and point out the differences 

 between the two forms ; and if I separated them specifically 

 I should probably be corrected by those who have the oppor- 

 tunity of comparing very large series from different countries 

 and seeing how they run into each other. In treating C. albo' 

 notatus as a subspecies of C. macrurus, I believe that I do 

 full justice to the fact that there are two forms which, in a 

 large area, where their habitats come together, form inter- 

 mediate links, and cannot therefore be regarded as *' good " 

 species. Not only are the Australian specimens, as Oates 

 justly mentions, very small, but all those from the islands 

 (Java, New Britain, Aru Islands, &e.) are as small as those 

 from Australia. I shall therefore call the southern form 

 C. macrurus, Horsf,, and the Indian race C. macrurus albo- 

 notatus (Tick.). 



Specimens of C. macrurus from North Borneo are very 



