267 
1921.] Birds of Tasso and adjoining Islands. 
H.M.S. f Dwarf/ in lat. 10° O' N., long. 15° 30' W., on June 
14th, 1920, while the gunboat was at sea off Portuguese 
Guinea. Mr. Lowe skinned the little bird, and it proved to 
be a new race, which I named Sarothrura bohmi danei in 
honour of Lieut.-Commander Dane, R.N., of li.M.S. ‘ Dwarf 3 
(cf. Bull. B. 0. C. vol. xli., Oct. 1920, p. 3). 
Another bird, the identification of which has been anything 
but easy, figures in my list as Sterna [species undetermined] 
?dougalli , Mont. The Roseate Tern. This is a most remarkable 
specimen, which has puzzled several ornithologists to whom I 
have submitted it. Dr. Hartert has, I believe, come nearest 
to identifying the bird ; he writes “ I should describe it as a 
gigantic specimen of Sterna dougalli with abnormally deep 
cleft feet.” He notes that Sterna dougalli gracilis of Australia 
sometimes has wings as long as this. Unfortunately, the 
Tern under discussion, which Mr. Lowe shot in Freetown 
Harbour on the 5th May, 1920, is an immature female, 
apparently about eleven months old, with bill and feet black. 
The primaries are very worn, and the shafts broken off at 
the end ; and taking this fact into consideration the wing- 
measurement of 233 mm. is remarkable. Had the wings not 
been damaged, the measurement would have been somewhere 
between 235-240 mm. The bird is in full moult, and has 
attained its new tail-feathers and some of the secondaries. 
If it is indeed a specimen of the Roseate Tern, its occurrence 
so late as May in Sierra Leone is difficult to explain. The 
bird is recorded from one or two localities on the East 
African coast as far as Cape Town, but I know of no example 
having been taken in West Africa. Mr. Willoughby Lowe 
believes that it will prove to be a resident and probably 
distinct breeding-race, but until its breeding-ground is dis¬ 
covered nothing further can be done. I would specially 
draw the attention of any ornithologist who may be quartered 
at Freetown! to securing more specimens, and particularly 
of ascertaining whether any Roseate Terns visit Freetown 
Harbour. 
Mr. Lowe has reported the existence on Tasso Island of a 
fine Ground-Hornbill (Bucorvus), which from his description 
t 2 
