Some Habits and Hosts of Bird Ceratophylli. 85 



presented to Mr Rothschild, in whose honour this fine species is 

 named. 



C. rothschildi has apparently affinities in two directions. On the one 

 hand, it is related to the gallince group, e.g., with dalei in the shape 

 of the 8th sternite $ . The 8th tergite $ is also of the type usual in this 

 group. On the other hand, there are even more obvious links between 

 the present species and the recently named G. frontalis, Eothsch., " which 

 is unlike any other described Ceratophyllus." 1 With frontalis, rothschildi 

 agrees in the strongly tuberculate frons of both sexes (though frontalis 

 seems to have this feature more pronounced) ; in the number of spines 

 in the pronotal comb ; but specially in the movable finger of the clasper 

 ( $ ) which has the same general shape in both species, the most noticeable 

 difference between the two being that while in frontalis there is one 

 peg-like spine at the distal angle, there are in rothschildi two. C. frontalis 

 was described from specimens taken in a nest of the Alpine Chough 

 (Pyrrhocorax alpinus). Possibly, as has been suggested to me, G. rothschildi 

 may be the flea of the Common Chough (P. graculus) which has transferred 

 its attention to a new host when the old became extinct in this locality. 

 An exchange of the kind might easily occur in the case of birds which, 

 like the Chough and the House-Martin, nest in cliffs. There seems, 

 however, to be no evidence that the Chough has at any time bred in 

 Kincardineshire. The St Abb's station, according to Howard Saunders, 2 has 

 long since been deserted. 



Census of Fleas, etc, from Martins' Nests, Kinneff. 



C. farreni. C. dalei. C. rothschildi. 



$ $ 1672 none 7 



? £ 2368 40 2 



There were besides about a dozen puparia of Stenopteryx hirundinis, 

 Leach, in the debris of the nests. Few acarids occurred, but some 

 lepidopterous larvte were present and one or two Beetles. 



Thus out of over 4000 examples of farreni 41-38 % were $ $ , which 

 agrees fairly closely with a previous 3 estimate of the proportions of the 

 sexes in the species, based on a much smaller number of specimens. 

 Apart from the larger series counted, the present percentage ought to 

 be more accurate since the bulk of these imagines had just emerged from 

 the pupa. The occurrence of one sex only of dalei is noteworthy and 



1 Novitates Zoologicce., vol. xvi., May 1909, p. 58. 



2 Manual of British Birds, second edition, 1899, p. 230. 



3 Ann. Scot. Nat. Hist., Oct. 1909, p. 228. 



