BIRDS OF ETHIOPIA AND KENYA COLONY 313 



Order MICROPODIIFORMES 

 Family MICROPODIDAE 



MICROPUS APUS SHELLEYI (Salvador!) 



Cypsehin shelleyi Sai-vadoiu, Anu. Mus. Civ. Genova, vol. 26, p. 227, 1888: 

 Deinbi, Shoa. 



SpeciTnens collected: 



Male and female, Hawasli River, Ethiopia, February 12, 1912. 



Both specimens are in dark, fresh plumage. 



The material available for study is not sufficient to warrant a re- 

 vision of the races of this swift. Consequently I follow Meinertz- 

 hagen ^° and Sclater.^^ The so-called forms roehll Reichenow "^ and 

 nakuruensis Van Someren ^^ are based on seasonal and individual 

 variations, and are to be considered as synonyms of shelleyi. There is 

 a great difference in color between fresh and worn plumages of this 

 bird, the latter being much lighter, more brownish, less blackish than 

 the former, the difference being of the same magnitude as that found 

 between races and even species of swifts. Consequently it is clear 

 that caution must be used in describing new forms in this group. 



Furthermore, the fact that birds similar in every way, except in 

 intensity of pigmentation, are found together does not necessarily 

 imply two specific entities. Thus, Lynes ^* writes of swifts in gen- 

 eral in Darfur that, " * * * on present evidence, positive and 

 negative, it is reasonable to suppose that a number of individuals 

 of all three Palearctic species do not breed, but remain in Africa 

 every year. Their numbers are too great for these birds to be 

 regarded as merely nonbreeding derelicts; that is, as exceptional, 

 injured or sterile birds, hanging about in odd places while normal 

 birds of their species are breeding elsewhere. They may, like 

 enough prove to be yearling birds (9 to 12 months old), some or all 

 of which are not sexually vigorous enough to breed, as we have 

 recorded to be evidently the rule with yearling birds of some of the 

 Weaver-Finches * * * " It follows, therefore, that J'oung of 

 Micropus apus apus or of Micropus apus pekinensis may occur in 

 breeding colonies of Micropus apus shelleyi. Some such state of af- 

 fairs is probably the solution of the rather astonishing statement of 

 Van Someren's ®^ that 31. shelleyi, M. roehli^ and M. nakuncensis (as 

 well as M. hoims and M. strevheli) nest together or in close proximity. 



'"Ibis, 1922, p. 36-42. 



»i Syst. Avium Ethiop., 1924, pp. 2.56-257. 



^ Orn. Monatsb., vol. 14, p. 172, 1906 : Usambara Mts. 



»3Bull. Brit. Orn. CI., vol. 40, p. 58, 1919: Nakuru. 



"Ibis, 1925, pp. 360-361. 



"^Nov. Zool., vol. 29, 1922, p. 88. 



