109 



proofs that the bh'd colony furnished them with abundance of fattening food. 

 The following year this locality was abandoned by the shags, who established 

 themselves on a swamp by the Purakanni ; this likewise was deserted at the 

 next breeding season. Why 1 If this change of quarters was rendered 

 necessary by the presence of vermin or filth, how is the guano island built up, 

 iinless, indeed, the salt breezes of the ocean befriend the birds by destroying 

 their parasitic tormentors. 



Art. XII. — Notes on an Egg of Alca impennis, Linn., in the Collection of 

 the writer. By T. H. Potts. 

 [Read before the Wellington Philosophical Society, July 16, 1870.] 

 Alca impennis, Linn. ; Great Auk, or Gare-fowl ; the Geir fugl of the 

 Icelanders; — is the rai'est of the Alcidce, and pi"obably also, it is the rarest 

 bird of the northern hemisphere. 



Various authors have described it as living, except during the breeding 

 season, almost habitually at sea, where its wondrous powers of swimming and 

 diving procured for it a constant supply of food ; we know from good authority 

 that formei-ly it was to be found at St. Kilda, the Oikney and Faroe 

 Islands, Iceland, etc., but however numerous the flocks then met with, in 

 various parts of the stormy northern seas or its rocky ice-bound shores the 

 Gare-fowl rapidly became scarce. Perhaps its numbers were diminished to 

 satisfy the craving appetites of half-frozen whalers and sealers, whose visits 

 too would most probably take place during the breeding season, when the brief 

 summer opened up a track for the vessels through boisterous seas, haunted 

 with floating icebergs. I think Henry Hudson, the old navigator of those 

 inclement seas, intended the Gare-fowl when he wrote : — " They killed and 

 brought with them a great fowle, whereof there were many and likewise some 

 eggs." There was evidently no close time or fence month obsei-ved for the 

 Great Auk; bird and egg was equally welcome to those "toilers of the sea." 



So rare at last became this sea-fowl, that the only specimen the British 

 Museum possessed for many yeai's, was the bird obtained by Mr. Bullock, and 

 which was purchased at his sale, May, 1819. The curious naturalist will find 

 in the catalogue of that great sale of zoological curiosities : — "Lot 43 ; Great 

 Auk (Alca imjoennis), a very fine specimen of this exceedingly rare bird, killed 

 at Papa Westra, in the Orkneys, the only one taken on the British coast for 

 many years," etc. 



So long a period has elapsed since a living specimen has been observed, that 

 many naturalists, amongst them Professor Owen, are inclined to regard its 

 extinction as an accomplished fact, for, notwithstanding the scientific exploi-a- 

 tions, more or less exhaustive, which have characterized the various Arctic 

 expeditions, not a single instance of the occurrence of the Gare-fowl is recorded. 



From notes and observations of various travellers, sportsmen, and collectors, 



