198 MR. E. C. STUART BAKER ON 
the same flock, is so great, that extremes of variation can be obtained 
from the same area if a sufficiently large series is available for 
examination. In the present instance, of the three birds collected by 
Mr. Herbert, two are quite typical frontalis, whereas the third specimen 
is an equally typical saturatior. The series under the name of 
saturatior in the British Museum consists, with one exception, of very 
poor, dingy skins ; the one clean exception, however, is no darker than 
are other skins of frontalis from Assim, Sikkim and Ceylon. Certainly 
the white on the throat of these three Siam birds is very restricted, 
but not more so than in some specimens from the countries already 
named, and this characteristic seems of little, if any, more value than 
the others. 
49. DICRURUS ANNECTENS SIAMENSIS. 
Dicrurus annectens siamensis, Kloss, Ibis, 1918, p, 226, 
¢ Tung Song, P. Siam, 23. 10. 15. 
2 Krabin, C. Siam, 2. 11. 15. 
Kloss has recently (loc. cit.) described the form of Crow- 
billed Drongo found in Siam as new, and has given it the name 
of D. a. siamensis. ‘The character on which he founds his sub-species 
is the alleged smallness of its bill, which measures in breadth at the 
nostrils 8.7 mm. and in height at the chin 8.6 mm. The two birds 
obtained by Mr. Herbert undoubtedly confirm Kloss’ diagnosis, as far 
as they ,o; the bird obtained at Krabin, a place some eighty miles 
BE. N. E. of Bangkok, has a very small bill of only 8.3 mm., and the 
other specimen from Tung Song, about 400 miles 8. of that place in 
Peninsular Siam, has a huge bill of no less than 10.3 mm. On the 
other hand I find that there is an immense range of variation in 
specimens from practically every portion of the area inhabited by this 
species, from the Himalayas to the extreme South. In nearly every 
district the range in variation of breadth is from 9.5 to 11.5 mm., 
but if an average is taken, it is very level throughout. 
For the present, therefore, 1 retain the smaller of these birds 
under Kloss’ name siamensis. 
50. DickURUS LEUCOGENYS. 
Buchanga leucogenys, Walden, A, M, N, H, (4) vy, p. 219 (1870). 
? Maprit, P. Siam, 28. 12. 15. 
JOURN. NAT, HIST. SOC, STAM, 
