GEOCICHLA DISSIM1LIS, BLYTH. 103 



one, and there is every reason to believe that it is in Ceylon 

 a purely migratory bird finding its way at intervals during 

 the cold season from the mainland to Ceylon. 



When we come to the question of separating G. andamanen- 

 sis and G. albogularis, we enter on more doubtful ground. 



As I said long ago, taking the birds from both islands as a 

 body, it may correctly be said that the Nicobar birds are more 

 deeply coloured, and have more white on the throat than the 

 Andaman ones ; but where both the colour and the amount of 

 white on the throat in the birds from both islands vary as they 

 do, there must, according to my view of what constitutes a 

 valid specific difference, be a constant superiority in respect to 

 points like these, of all the birds of one race over all the birds 

 of the other. There is no such constant* difference in the case 

 of these two supposed species. On the contrary, we have Anda- 

 manese birds as deeply coloured, and showing as much white 

 on the throat as several of the Nicobar birds ; and if the whole 

 lot be thrown together, and the tickets removed, there are at 

 least one in five of which no one on earth could predicate whe- 

 ther it came from the Nicobars or the Andamans. Here, again, 

 if Mr. Seebohm considers it right to maintain two species, I 

 can only record my dissent and warn my readers against 

 what I consider to be hair-splitting, valde deflendus. 



torMta toimilia, IJtgtft. 



In consequence of Mr. Seebohm's remarks on the above 

 species, I applied, through my friend Mr. Wood-Mason, who is 

 always anxious to help in clearing up every difficulty, to the 

 Trustees of the Calcutta Museum, for the loan of Mr. Blyth's 

 own specimens, of this species six in number, entered in his 

 Catalogue at page 163, No. 955, 1 male and 5 females. 



They very kindly acceded to my request, but informed me 

 that two had been probably destroyed and one lost. 



When years ago I examined these birds there were six of 

 them, all in a row on one board, and these were then all with- 

 out exception Geocichla imicolur, Tick. 



Now the three remaining specimens are mounted each on small 

 separate stands. Two are still unicolor — the third is un- 

 doubtedly a young male or female of the species that I named 

 tricolor. 



* Note too that from the Little Cocos, an island belonging to the northernmost 

 portion of the Andaman Group, we have a specimen with a throat almost whiter 

 than any specimen from the Nicobars. 



