252 
Letters , Announcements, tyc. 
The great distinction, however, between B. castaneus and 
B. affinis is in the form of the bill, which is much smaller in 
the former, measuring in all three specimens about 1*05 in. 
across at the gape, whilst in the three specimens of B. affinis 
it measures 1/4 in. B. castaneus, however, is rather the 
larger bird of the two, the wing measuring 5*2 to 5*5, whereas 
in none of the specimens of B. affinis examined does the wing 
exceed 54, and in one it is only 4*5, as in Blythes original type. 
The female bird already noticed as agreeing in general 
coloration with Otothrix hodgsoni agrees fairly in all its di¬ 
mensions with Batrachostomus castaneus, and may be the 
female of it. Otothrix was separated from Batrachostomus by 
Mr. Gray on account of its smaller bill and different colora¬ 
tion ; and although the shape of the bill in the figure (P. Z. S. 
1859, pi. clii.) is totally different from that of Batrachostomus, 
no mention of any such startling difference is made in the 
text, and I see that Lord Tweeddale, in Blythes Catalogue of 
the Birds of Burma, p. 83, has referred O. hodgsoni to Batra¬ 
chostomus, so that it is probable that the representation of the 
bill in the figure is defective. On the whole I think that 
Mr. Hume's suggestion that B. hodgsoni and B. castaneus 
are the two sexes of one bird is highly probable. The young 
bird has the grey mottled plumage of B. hodgsoni, which is 
in favour of the latter being the female. 
Of the two specimens from Travancore, referred by Mr. 
Hume to B. moniliger, the female agrees on the whole fairly 
with Mr. Blyth's description (J.A. S.B. xviii. p. 806) both 
in coloration and dimensions. These skins will be fully de¬ 
scribed by Mr. Hume in a forthcoming number of f Stray 
Feathers/ Both differ greatly from B. punctatus, being much 
larger, with bills measuring fully P4 across at the gape, 
whilst the breadth in B. punctatus is 1*25. In the latter the 
wing measures 4*35, and the tail 3*9; in the female of B. mo¬ 
niliger, which approaches nearest in plumage to B. punctatus, 
the wing measures 4*8 and the tail 4 inches. The whole 
plumage in the latter is browner; and although the difference 
is much less than in the case of B. affinis and B. castaneus, 
I certainly think that B. moniliger and B. punctatus are dis¬ 
tinct forms. 
