1900.] EROll BRITISH EAST AFRICA. 939 



the secondaries marked as in P. tibullus 2 ; on the under surface 

 the apical area of the primaries and external area of secondaries 

 are broadly grey-brown ; the inner half on the primaries forming 

 an externally diffused black belt upon which the pale patches and 

 spots of the upper surface are sharply outlined : the internal half 

 on the secondaries merely darker brown ; veins and internervular 

 folds dark brown. Expanse of wings 100-103 millimetres. 



95. Papilio cenea. 



2 . Papilio cenea, Stoll, Suppl. Cramer, p. 134, pi. xxix. tigs. 

 1, la (1791). 



d d,2 2, Nairobi forest, March 11, 18, & 20, 1900. 



d . " Common in the forest at the foot of the escarpment and 

 easily taken, its flight being sluggish and almost always well 

 within reach of the net. 



"In an hour I saw perhaps twenty-five or thirty, flying along 

 between the trees or hovering over some flowering bush : I netted 

 six, two of which had their tails entire. This insect does not relish 

 or frequent open country, though occasionally I have seen one here 

 and there out on the plains fully a mile from the forest, when 

 obviously it is anything but in its element, as its flight is then 

 absolutely regular and horizontal with the ground, and within five 

 or six feet of it, hurrying for all it is worth. In the forest its 

 flight is lazy ; it often stays to hover and returns over and over 

 again over the same ground and the same bush. 



" Quite a common characteristic of its flight is a perpendicular 

 drop of ten, fifteen, or twenty feet : it closes its wings and falls 

 straight away." (R. G.) 



2 . " Pale sea-green spherical ova." (R. G.) 



Of a male obtained on March 18th Mr. Crawshay writes : — 

 " Very plentiful nowadays. At a water-hole I saw to-day a 

 number of this species and about a dozen of the black velvet and 

 metallic blue coloured Swallow-tail (P. nireus) feeding on the moist 

 ground in company with each other." 



Of a female (white-spotted P. cenea type) he writes — " Have 

 seen and netted several specimens, but not one is perfect.'* Lastly 

 of a female (P. tibullus type) — " There could be no easier insect 

 to take than this." 



96. Papilio phorcas. 



d . Papilio phorcas, Cramer, Pap. Bxot. i. p. 4, pi. ii. B, C 

 (1775). 



2 . Papilio ihersander, Fabricius, Ent. Syst. iii. pt.l, p. 32 (1793). 



d , Nairobi forest, March 11 ; d d , 2 2 , Buarka Biver, April 

 22 & 27, 1900. 



d . " Common in the forest, and, I suppose, a very common 

 insect in other African forests ; it is not easy, however, to secure 

 a perfect specimen." 



2 . "As far as I know this Swallow-tail is new to me. Close 



t> 



