| OCR Text |
Show 1886.] MR. R. COLLETT ON HYBRID GROUSE. 233 again to his gun. The knowledge of its life and habits therefore amounts to almost nothing, and no observations have been made in Norway which can give any information concerning its origin. The existence of this hybrid arises from the fact that both parents not unfrequently inhabit the same localities. Thus Tetrao tetrix in the southern valleys of the land, where most of these hybrids are met with, regularly ascends to the elevated birch-forests on the mountains, and establishes itself in the regions where Lagopus albus has its proper home. On the other hand, but more rarely, Lagopus albus descends and breeds in the upper portions of the conifer-woods, where the other species is still to be met with in numbers. In the northern portions of the country, however, where both species live almost at the same elevation above the sea, and still more commonly share the same place of residence, the Tetrao tetrix on the whole appears in much lesser numbers than the other species, and the hybrids are here apparently more rare. It is not easy to understand the true reason for the pairing between two species so different in their habits, appearance, and nature. One of the specimens obtained in Norway was shot at a place (Saltdalen in Nordland) where no want of mates of either species could be observed in the neighbourhood. Connections of this kind are repugnant to nature, and in many cases the only feasible explanation is to be found in imagining a violent and irresistible desire to breed out of the species. Concerning the question of the origin, it is first of all necessary to find out whether one or two sorts of such hybrids exist-the one bred between the male Lagopus albus and female Tetrao tetrix, the other between the male Tetrao tetrix and female Lagopus albus1. But as it is an established fact that all individuals hitherto found (with us) of the Rype-Orre, if obtained at the same season of the year, are on tbe whole singularly alike both in size and the colouring of their plumage, their origin cannot be ascribed to more than one of the two possible connections. When Prof. Nilsson in 1817, in his ' Ornithologia Suecica,' treated of its descent for the first time, he mentions it (p. 303) as " Hybridus a Tetrice patre et Tetr. subalpino femina" \ This assumption that it is the male of Tetrao tetrix which has formed an illegitimate connection with the female of Lagopus albus (as it is also the Blackcock that with the female of Tetrao urogallus produces the " Rakkelfugl"), has always been and is still generally accepted by most naturalists. Upon this theory it has received the names:-Tetrao lagopoides, Nilss. Skand. Fauna, 1st ed. (1828), and Tetrao lagopides, 2nd ed. (1835) ; Tetrao lagopodite-tricides, Sundev. Svenska Fogl. p. 255 (186-?), (being the descendant of Tetrao tetrix, mas, it had to bear its generic name) ; and, finally, 1 A hybrid between Lagopus mutus and Tetrao tetrix is rather improbable, on account of the very different haunts of these species. 2 " Qui vero videt (illas) varietates, non diutius dubitare potest de libidine Tetricis ad furtivos amores cum congeneribus instituendos semper paratissima.'' (Nilss. I. c.) PROC. ZOOL. Soc-1886, No. XVI. 16 |
