176 Bhort hlotes. [Ibis,

Motaoilla flava beema in Northern Rhodesia. Your notice of Dr. Winterbottom’s “ Revised Check-List,

of tho Birds of Northern Rhodesia” (Ibis, 1940, p. 569) contains a reference to a Wagtail recorded by Dr. Winterbottom as M . flava beem, and states that the bird “ is more likely to be Hotacillu $am jlavu ”. I have looked up the specimen (which your reviewer is right in supposing to be in this Museum), and it is undoubtodlj a male beema. In fact it is an almost exaggerated example-the crown a very pale pure grey, almost white in front, and the cheeks very pale too. The tail measures 71 mm. It was collected on 3 March, 1905, and appears to have been in fresh summer plumage. E. L. GILL

(Director, South African Museum, Cape Town).

“ Duetting ’’ in Birds. Louis Agassiz Fuertes, in his “ Impressions of the Voices

of Tropical Birds ” (Smithson. Rep. 1915, pp. 299-323, reprinted from ‘ Bird-Lore ’, xv. no. 6), refers to “ countersinging by the €emale ” of a pair as “ not generally known among birde ”. He goes on to remark that i t is practised, however, by all the forms he knows of Pheugopediwr, Henicorhina and Donucobius, as well as by Heleodytee bicolol.. So far as I know and can ascertain by enquiry among friends who know Pnlaearctic birds altogether better than I do myself, duetting is unknown amongst them ; but several instances of Mrican species have come to notice where both birds of a pair sing in unison or a second bird, known or presumed to be a female, regularly joins in with some particular note or phrase at a definite point in the song.

The most striking instahce is afforded by the Barbet, Trachyphonus d’arnaudii bohmi, where the female contributes a monotonous clinking note (and “ dances ” too) while the male is repeating his phrase (Ibis, 1937, p. 170). Courting Heterotrogon v. vittatum also collaborate in a “ song ” ; one utters a sequence of yelping notes, the other regularly joins in about half-way through, and continues after the &st has