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Show 46 MR. R. COLLETT ON PHYLLOSCOPUS BOREALIS. [Feb. 6, ductive of those insects, m y investigation of their general habits was rendered extremely difficult. It was absolutely impossible to keep still a moment, the veil not only affording insufficient protection against their continuous attacks, but being in other respects obstructive to minute observation. The food, too, of Ph. borealis, at this season of the year, would seem to be wholly taken from these countless myriads ; and the ventricles, in all the specimens examined were crammed with these insects. There are at least half a dozen species of these mosquitos, all more or less numerous, though some outnumber the others in particular localities. On one occasion (July 22) I may have been close to a nest, on the Pasvig Elv, near Lake Tschoalme-javre, South Varanger. Both the parent birds exhibited unmistakable signs of alarm; but here, too, the mosquitos prevented me from finding the nest. A female shot in another locality on the same river had large incubation-spots. I prepared in all 5 specimens, 4 of which were males. Both sexes were, in regard to colour of plumage, precisely alike. A very slight difference was seen in some of the males, the dorsal feathers being in some darker than in others, and the eye-stripe in such specimens was a trifle whiter. They measured as follows :- Total lengtb. Wing. Tail. Tarsus. Gape. millim. millim. millim. millim. millim. d* 132 70 52 20| 15| 6 67 50 6" 67 48| 20 15i 6" 135 71 50 20i 16 5 123 63 44^ 20 15 The female would thus appear to be somewhat smaller than the males, a deduction in accordance with Mr. Meves's measurements of a number of specimens obtained at Kopatjevskaja, south of Archangel, on the 8th and 9th of August, 1869 (Oefv. Kongl. Vet. Akad. Forh. 1871, p. 758), whereas, on the other hand, there was a singular and almost invariable discrepancy between the Russian and Finmark specimens, the latter appearing to have been all somewhat larger than those from Archangel. Middendorff has before observed that the back of specimens taken in the middle of the summer, when the plumage is somewhat worn and faded, has lost a little of its vivid green colour and has acquired a greyer tint; this was likewise the case with all the Finmark specimens, which, besides, scarcely retained a trace of the whitish yellow spots at the extremities of the wing-coverts that in autumn and early spring give to the wings a yellowish band. The first primary in one specimen was a trifle shorter than the coverts, in the others of the same length, or very little (I millim.) longer. The synonymy and general distribution of the species I shall refrain from dwelling upon here, m y friend Mr. Dresser purposing, I understand, to treat upon that subject at large in his great work |