47 



dimensions, which does not belong to any of the preceding species. 

 The bill is reddish on the root ; the under parts are lighter than on 

 the young cay anus ; the stripes are more obsolete, and are reduced 

 on the side as black shaft-stripes ; shafts of the tail reddish brown ; 

 under tail and interior wing-covers white, without spots. 



Ps. cayanus. Ps. maximus. 



Dimen. — Head 52 .56 



Gape 35 35 



Wing 129 129 



Tail 70 73 



Height of the bill 11 13 



Breadth 12 13^ 



It would be very interesting to discover the old bird of this species. 



d. Subgenus Erator. 



It unites the size, colouring and formation of the second hand- 

 feather of the true Psaris with the bill and feathered lorum and eye 

 region of the other subgenera. 



This little subgenus, with its mixed characters, gives the clearest 

 proof that Psaris, Pachyrhatnphus and Bathmidurus caiuiot be con- 

 sidered as true genera. 



12. Ps. iNauisiTOR, Orb. Lanius inquisitor, Olf. 

 Diaff. — Tail black. 



Descr. — The male with black head and white ear-covers, connected 

 with a white collar, which divides the black head from the silver-grey 

 body ; tail black, at the root white, which extends to the margins of 

 the inner webs ; end of the tail without white band; the second hand- 

 feather on the inner web white. 



The female (Jardinii, erythrogenys, Selbyi, and Nattereri, Sw.) 

 with white front and rufous ear-covers. 



13. Ps. Fraserii, Kaup. (Aves, PL XXXVII. XXXVIII.) 

 Diag. — Tail two-thirds white, with black white-bordered end. 

 Descr. — The head to the ear-covers black ; ear-covers and under 



the posterior part of the eye white ; the second hand wing-feather 

 light ash-grey, with white root. 



The dimensions of these two species are nearly the same : — head, 

 52; gape, 32; height of the bill, 10; breadth, 14-15; wing, 105- 

 113; tail, 63-70. 



I give to this very distinct species the name of a very able zoolo- 

 gist, who is going a second time to Western Africa. From this jour- 

 ney we may anticipate the greatest benefit to our science, and we wish 

 Mr. Fraser the best success. For all his kind assistance m the col- 

 lection of Lord Derby I give him my best thanks. 



e. Subgenus Bathmidurus, Cab. 



They have the bill like Chloropsaris, Pachyrhamphus and Erator, 

 but the tail in most of the species is more graduated. The colouring 



