PERNIS TWEEDALII, HUME. 447 



agreeing with the description of the Malay female; the 

 feathers of the forehead are mostly edged with a similar grey 

 tint instead of with white as in the Malay male. 



None of the feathers of the crest in the Sumatran bird are 

 tipped with white, and as far as appears, none of those of the 

 nape, but many of the latter are missing. 



The dark bars across the primaries are broader in the 

 Sumatran specimen, the broadest being an inch in breadth, 

 but only '8 of an inch in the Malay male. 



The Sumatran female also differs in having the paler brown 

 interspaces on the outer webs of the secondaries tinged with 

 grey. 



The Sumatran bird has the principal dark tranverse bars on 

 the tail broader than those in the Malay male, and four in 

 number instead of five, the subterminal band being 2' inches 

 across, and the band next above it being 1*5, whereas the 

 breadth of each of the corresponding bands in the Malay 

 male is a trifle under one inch, and in the Malay female 

 (as given by Mr. Hume) 23 and 2. 



The dark line along the centre of the throat in the Sumatran 

 female, though slightly irregular towards the chin, is well 

 marked, and about "2 in width at the lowest part which is the 

 broadest. 



The rufous tinge on the paler portions of the feathers of 

 the upper breast is more decided in the Sumatran bird than in 

 the Malay male, and is also less limited to the sides of the 

 breast. 



The cross barring on the breast and abdomen of the Suma- 

 tran specimen is more fully developed than in the Malay male, 

 which I attribute to its being an older bird, and agrees with 

 Mr. Hume's description of the Malay female, except that none 

 of the pectoral and abdominal feathers have less than three 

 dark cross bars, and some of the latter have a fourth less dis- 

 tinct bar near the base. 



In the Sumatran female the dark transverse bars are slightly 

 broader on the abdomen than in the Malay male, and very 

 decidedly so on the thighs and under tail-coverts. 



The peculiarities of this specimen from south-east Suma- 

 tra did not escape the observation of the late Lord Tweeddale 

 (vide Ibis, 1877, p. 286), but he felt a hesitation, in which 

 I concurred, in describing it as specifically distinct from 

 its very variable congener P. ptilorhyncJius on the strength of 

 only a single specimen. The subsequent acquisition by Mr. 

 Hume of two similar specimens appears to me to remove the 

 grounds for such hesitation, and to prove that there exists in 

 Sumatra and in the Malay Peninsula a Pernis distinct from 

 P. ptilorhi/nchus and intermediate between that species and 



