134 Mr. H. Seebolim on the Genus Scolopax. 



stead of sixteen tail-feathers '^^ and on an average a larger 

 foot ; l)ut it is doubtful whether the latter character would 

 hold good in a large series. As it is_, the difference is so 

 small that, in order to make it as perceptible as possible, it 

 is necessary to measure the foot in the longest possible way, 

 that is, from the joint of the tibia and tarsus to the end of 

 the claw of the middle toe. These dimensions vary in S. no- 

 bilis from 3'0 to 3"3 inches, and in S. macrodactyla from 3*4 

 to 3"6 inches. So far as is known, the Madagascar Snipe is 

 the only Snipe found on that island, and does not occur on 

 the mainland. 



The explanation of the apparently extraordinary fact that 

 two such veiy closely allied birds inhabit such widely distant 

 localities appears to me to be as follows : — Their nearest rela- 

 tive is unquestionably Latham^s Snipe, which occupies a 

 locality midway between them. The latter is a migratory 

 bird, breeding in Japan and wintering in Australia; but 

 there cannot be much doubt that it was once a resident in 

 Japan, nor that a change in the habits of a bird from 

 being a resident to being a migrant with a range of migra- 

 tion covering a distance of five thousand miles soon pro- 

 duced a corresponding change of structure. Its rounded 

 wings and exceptionally long and heavy bill must seriously 

 have impeded its progress, and we may confidently assume 

 that Natural Selection soon lengthened the one to aid its 

 powers of flight, and shortened the other so that it might 

 have less weight to carry. What I wish to be inferred from this 

 argument is the strong probability that Latham^s Snipe — be- 

 fore it became a migratory bird — differed scarcely, if at all, 

 from the present condition of its allies in Madagascar and 

 Colombia. The cold of the Glacial epoch not only forced it 

 to winter in Australia, but so reduced the area of its breed- 

 ing-grounds that large bodies were compelled to emigrate in 

 search of fresh breeding-places, as Pallas's Sand-Grouse did 



* Even this character appears to be douLtf ul, as Messrs. S. Rocli and E. 

 Newton (' Ibis,' 18G3, p. 172) state that the normal number of tail-feathers 

 of the Madagascar Snipe appeared to be sixteen. I have never seen an 

 example in which there were more than fourteen. 



