•276 BIRDS! OF BRITISH GUIANA. 



Key to the Specie". 



A. Upper parts paler ; superciliary line and 



nuchal collar buff ; sides of face parti- 

 coloured; lower abdomen and sides of body [p. 276. 

 rufescent buff F.Jiisco-carulescens, 



B. Upper parts darker ; no suiwrciliary line or 



nuchal colllar; sides of face uniform. 

 h. Smaller, wing less than 220 mm. ; breast 



similar in colour to the abdomen ; lower 



abdomen, thighs, and under tail-coverts 



uniform in colour F. ru ^gidaris. p. 277. 



c. Lriirger, Axing more than 220 mm. ; breast 



chestnut, in contrast to the abdomen ; 



abdomen, thighs, and under tail-coverts 



jtarti-colouivd F. deiroleucus, p. 278. 



174. Falco fusco-caerulescens. 

 Aplomado Falcon. 



Fidco fiisco-ccrrulescens Yieill. X. Diet. d'Hist. Xat. xi. p. 90, 1817 



(Parairuav) ; Shaqje, Cat. B. Brit. Mus. i. p. 400, 1874 ; Brabourne 



& Chubb,' B. S. Amer. i. p. 78, no. 6G9, 1912. 

 Hi/potriorchis femoral is Cab. in Schomb. Keis. Guijin. iii. p. 734, 1848 ; 



Salvin, Ibis, 1886, p. 76 (Koniima, 3500 ft.) ; Quelch, Timchri (2) 



vi. p. 129, 1892. 



" Slate-backed Hobby " (Quelch). 



Adult male. Upper parts dark slate-orey, darker on the crown of 

 the head and sides of the face ; upjjer tail-coverts and tail barred 

 with white, tail-feathers blackish in contrast to the back ; primary 

 and secondary quills barred with white on the inner webs, inner 

 ]»riniaries and secondaries margined with white at the tips ; a line 

 over and l)ehind the eye extending round the nape, edge of wing, 

 hinder cheeks, throat, and breast tawny-buff, the last streaked 

 with black ; abdomen and sides of body black, narrowly barred 

 with white; axillaries ami inner under wing-coverts similar, but 

 more broaiily barred or spotted with white ; lower abdomen, 

 thiuhs, and under tail-coverts rufescent butf. '' Cere and feet 

 vellow ; bill horn-brown, yellow at base.'" 



Total length 340 mm., cuhnen (including the cere) 21, wing 

 240. tail 144, tarsus 55, middle toe and claw 43. 



The male described was collected at Mount Roiaima by 

 Mr. McConnell in October 1808. 



Adult female. Similar to the adult male in the colour of the 

 plumage but larger in size. Wing 252 mm. 



Breeding-season. Unknown in British Guiana. 



yest. Unrecorded in British Guiana. 



J-l<his. Undescribed from British Guiana. 



