69 



through which all individuals of the latter pass before the arterial 

 blood-red hue is attained. 



3rd. The disposition of black or brown on the head, its taking the 

 form of a mask, as in L. capistratus, or as a hood, as in L. ridibundus, 

 is either transitional or accidental*, and the shade of colour com- 

 monly varies from the " broccoli-brovvn " of the former to the deejier 

 tint of the ordinaiy L. ridibundus. 



A specimen of the L. capistratus, purchased at the sale of Bullock's 

 collection by Dr. Leach, and beUeved to have been one of the first 

 birds seen by Temminck, to ■which he gavę this name, is now in the 

 British Museum. By the kindness of Mr. George R. Gray, 1 made a 

 critical comparison of this bird with the specimens now exhibited, 

 and, excepting in the smaller size of the toea and webs of feet, there 

 was no difference between it and some of them ; and from the adult 

 female, L. ridibundus, in full summer plumage it differed in the most 

 trivial manner only. 



* I have known it to be both transitional and accidental, i. e. for birds 

 to exhibit the mask the frst summer of their attaining adult plumage, and 

 otbers the hood in their first assumption of the black hood. 



