from th:-/i of P. clio of tlie Sula Islar.ds in the colovir of tlie 

 under surface^ Tvhich is pale buifisli brovrUj • lighter in the 

 middle of tlie abdomen, dnrker and broTvner on the chest, and 

 becoming mjore greyish on the tliroat. Under tail-coverts 

 buffy yellow. The young male is more rufous below and 

 darker on the back than the female,, which is olive-bi'own 

 above. J ad. \Ying 93, tail 73, culraen 18-19 mm. 

 ? ad. Wing 89 nnn. 



Hab. Burn. 



I consider all these yellow Thickheads to be geographical 

 repi'eseiita lives of one species. 



CoLVMBA MADA; SD. n. 



J . Bill yellow, red at base. Top of head and neck pure 

 grey, merging into the colour of the rest of the upper surface, 

 which is slate-colour Avith light grey borders to the feathers. 

 Kectrices deep slaty brown, with narrow pale brownish tips. 

 Bare skin round eyes red. Sides of head, throat, chest, 

 and breast buff, palest on the throat. Abdomen brownish 

 vinaceous ; under tail-coverts cinnamon. Feet and iris red. 

 T\'ing 229, tail 170, exposed portion of culraen 16 mm. 



$ . Like tlie male, but slightly smaller. 



Hab. Islt. IMada^ Burn. 



jMr. Haktekt also exhibited a new Thickhead, and cha- 

 racterized it as follows : — 



Pachycephala pexinsul.i:, sp. n. 



cJ . Top of the head ashy brown ; remainder of upper surface, 

 including tail, olive-green. Eemiges blackish; inner webs 

 with whitish borders; outer Avebs edged with greenish olive. 

 Lores ashy ; an indistinct pale buffy eyebrow. Sides of head 

 ashy brown. Throat white. Breast light yellowish grey, 

 with darker shaft-lines ; abdomen pale sulphur-yellow, with 

 dark shaft-stripes. Under wing-coverts white, with a faint 

 yellow tinge, those towards the bend of the vring brownish, 

 with a yellow tinge. Iris brown ; feet light bluish slate. 

 Bill brown. Wing 78-79, tail 63, culmen ]6-5, tarsus 

 20 mm. 



