Dr. Heuglin on some Birds of North-Eastern Africa. 407 



LII. — On new or little-known Birds of North-Eastern Afinca. 

 By Hofrath Theodor von Heuglin. (Part I.) 



(Plate XV.) 



I. Hypotriorchis castanonotus, sp. nov. 



H. miuutissimus, Cauda subgraduata : pileo, nucha, uropygio et 

 tectricibus alarum ciucreis ex parte ferrugineo limbatis : 

 fronte pallidiore : interscapulio, tergo et scapularibus casta- 

 neis : stria supra-oculari, regione parotica, fascia cervicali 

 transversa, tectricibus caudse superioribus et gastrseo can- 

 didis : subalaribus albis nigricante f "asciatis : rectricibus et 

 remigibus fusco-nigris albescente aut flavescente terminatis, 

 albo guttatis et transversim fasciatis : remige prima extus 

 albo marginata : long, tota 6'9, rostri ab angulo oris 0'5, 

 aljE 4-4|, caudfe 2-10^, tarsi 0-ll| poll, et lin. Gall. 

 Hab. In ripis Nili Albi. 



My specimens of this bird were procured in the mountains of 

 the watershed of Eastern Central Africa, from localities on the 

 Bahr el Abiad, beyond which no European traveller has yet 

 penetrated. The bird is scarcely larger in size than a Lark. At 

 the first glance it was considered as identical with Falco semi- 

 torquatus (Smith, 111. Zool. S. Afr. tab. 1). Considerable differ- 

 ences, however, were discovered after a more careful examina- 

 tion : e. g. the back is chestnut-brown in both sexes ; the colours 

 of the forehead and of the sides of the neck are different ; the 

 tail is somewhat graduated, whereas it is said to be slightly 

 rounded in H. semitorquatus, and is distinguished by a light- 

 coloured marginal band of nearly two liues in breadth. 



I give here the description of a male bird, certainly quite 

 adult. The head above and neck are cinereous, with a some- 

 what ferruginous shade ; the forehead is rather lighter (but not 

 quite white) ; the head below, a streak above and behind the eye, 

 the ear and the sides of the neck, and, finally, a band across 

 the neck, are pure white. Back and scapularies bright chest- 

 nut-brown ; rump and wing-coverts cinereous, partly margined 

 with reddish brown ; upper tail-coverts white, partly with cine- 

 reous longitudinal stripes. Wings and tail black, inferiorly dark 

 brownish grey, with white spots, each of which is interrupted by 

 the shaft of the feather and passes interiorly into transverse 



VOL. II. 2 F 



