239 5B 



with the female ptarmigan (Tetrao tdrix J and Lagopus albtis 9), is the 

 reputed father of so singular a progeny. Nilsson and most other or- 

 nithologists named this form Tctrao lago2)oides (or lagopides), 

 and Sundevall(„Svenska foglarne" p. 255), reasoning from the anal- 

 ogous facts recorded of the foregoing hybrid (vide .p. 236), letrao 

 lag op di- tetricides. 



In tracing the origin of this hybrid, which has hitherto almost 

 invariably occurred in but one dress and one sex, it is necessary 

 first to investigate, whether there be not two distinct forms 

 of „Rypeorre", the one bred between Tetrao tetrix t and Lagopus 

 alhus $, the other between Lagopus alhus t and Tetrao tetrix ?. 

 A similar hypothesis, as previously mentioned, has been started to 

 account for the parentage of the Rakkelhane; but the argument 

 proving its fallacy with that form of hybrid, holds equally good as 

 regards the „Rypeorre". Now, it is an established fact, that all 

 individuals of the Rypeorre-hybrid, if procured at any given season 

 of the- year, are singularly alike both in size and coloration of 

 plumage, and hence their origin cannot surely be traced to more 

 than one of the two possible connexions. 



As previously stated, the exertions of Swedish sportsmen and 

 naturalists' have provided ample proof of the true parentage of 

 the Rakkelhane. On one occasion, eggs taken from a brooding 

 letrao urogallus $, were incubated by a domestic hen, the issue 

 being a brood of Rakkelhons. Such a fact, taken in connexion 

 with the similarity of appearance presented by all individuals of 

 the Rakkelhane-hybrid, renders further evidence superfluous. 



So direct a proof of the Rypeorre has not yet been obtained, 

 and it must therefore be inferred from less conclusive facts. 



Nilsson having suggested in his Ornithologia suecica, Vol. I. 

 p. 303, the probability of the Rypeorre-hybrid being bred „a T. tetrice 

 patre et Tetr. suhalpino femina'', the conjecture has from that time to 

 this remained unchallenged. By reason of his tine plumage, 

 elegant form, and excess of vitality, Tetrao tetrix J has been able 

 to form these alien connexions. No other evidence, I believe, has 

 been advanced in proof of the assertion but the fact, that female 



