350 NOVITATES ZOOLOGICAE XXV. 1918. 



Hab. Gabun, Loango, Northern Angola, and the Congo basin to the Ituri 

 forest and Kindu, north evidently to Kamerun. 



Specimens from the Upper Congo (Kindu and 340 miles west of Baraka) 

 seem all to have the greyish tinge and are generally slightly lighter, while Ituri 

 forest birds are as dark as the darkest specimens from the Lower Congo and 

 Angola. Apparently also Princes Island. 



Ten skins from Princes Island in the British Museum, collected by Boyd 

 Alexander, 8 sexed " <J," 2 " $," agree in colour with T. calva calva. Their wings 

 are generally shorter, but some are as long as the majority of the latter, i.e. 

 153-160 mm. Though the isolated insular home suggests the j)robability of a 

 separate race, we must therefore unite the Princes Island birds with typical 

 calva, while Sao Thome has quite a different species, and Fernando Po a 

 distinct subspecies. 



2. Treron calva uellensis (Rchw.). 



Vinago calm uellensis Reichenow, Journ. /. Orn. 1912, p. 320 (" Jakoma uiid Koloka am Uelle "). 

 " Diese Form steht der Form F. c. sharpei vonder Goldkiiste mid Togo am nachsten und unter- 

 scheidet sich von dieser durch etwas helleren Ton der Gesamtfarbm-g. Sowohl das Griin dcr 

 Oberseite wie das Grau des Nackenbandes und des Schwanzes ist heller." 



One of us (Hartert) has examined in the British Museum a skin from Niam 

 Niam (Bohndorff coll.) and one from Toniaja, just south of the Uelle, which 

 agree with each other and differ from all other forms. They can hardly be 

 anjrthmg else than Reichenow's uellensis, though, by then- somewhat olivaceous 

 and indistinct nuchal collar, and less bright collars, they are perhaps better 

 compared with T. c. calva, from which they only differ by being lighter and 

 brighter, i.e. standing between T. c. calva and sharpei. 



Two birds from the Victorian Nile (one from Businde in the British Museum, 

 one from Fadjao in Tring) are also less brightly coloured than salvadorii and closely 

 resemble uellensis, while one from Kichuchu in Toro (Ansorge) also somewhat 

 resembles T. c. calva, but it is m worn plumage and not clean. Another 

 specimen from the Victorian Nile belongs to the eastern nudirostris — lilie form, 

 i.e. with a short naked space on the base of the bill ! 



3. Treron calva poensis subsp. nov. 



Specimens from Fernando Po differ from T. c. calva at a glance by their 

 paler, somewhat more yellowish underside, and generally slightly lighter upper 

 surface. Wing S ? 166-175 mm. 2 <?, 2 $ in the British Museum, Boyd Alex- 

 ander and E. Seimund coll., 1 " ? " (probably <J, wing 175 mm. !) in the Tring 

 Museum. Therefore apparently larger than T. c. calva. 



Type : " ? " (<? !), Bantabari, Fernando Po, 12. ii. 1904. E. Seimund coll. 

 (Tring Museum). 



4. Treron calva sharpei (Rchw.). 



Vinago calva sharpei Reichenow, Orn. Monalsher. 1902. p. 45 (" Oberguinea ") ; id., Vog. Afr. iii. 

 p. 806 (1905 — " Sierra Leone bis Kalabar "). 



Reichenow quite correctly restricted the name calva to the birds from 

 ■" Unterguinea " and considered pytiriopsis as a synonym ; Sharpe (Ibis, 1902) 



