KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 40. N:0 5. 75 



Prion banksi Gould 1844. 



f 



j Boiler Harbour, Cnmberland Bay, the lOtli of Nov. 1904. »Iris very dark brown, almost black.» 

 »Cauglit in the burrow, in the nest was 1 egg.» 



$ the same locality, the 22d of Nov. 1904. 



J 1 juv. the same locality, the 24th of March 1905, an almost fully fledged bird, cauglit iii the nest. 

 »Iris black.» 



1 pull. the same locality, the 20th of Febr. 1905, dug out from the nest. 



1 pull. the same locality. 



2 pull. fonnd on the deck of the vessel in Boiler Harbour, Cumberland Bay, the 5th of Febr. 1905, 

 cviilently dropped there by a Catharacta which was seen flying away. 



£ (skeleton) Moraine Fjord, Cumberland Bay, the 22d of Nov. 1904; cauglit in the burrow. 



ij (skeleton) Boiler Harbour, Cumberland Bay, the 4th of Dec. 1904; cauglit in the burrow. 



j" (skull) the same locality and date. 



1 egg, Boiler Harbour, Cumberland Bay, the 19th of Nov. 1904. 



1 egg, the same locality, the 13th of Dec. 1904. 



1 egg, » » » » 17th of Dec. 1904. 



1 egg (rotten) the same locality, the 14 of March 1905. 



The specimens recorded above must be referred to Prion banksi as the width 

 of the b ill is 14—15 mm. in aclult specimens, and the lamellse of the maxilla are 

 just visible at the rictus, when the bil] is closed. The bill of the just fledged young 

 is almost as wide, viz. 12,5 mm. The length of wing is 191 mm. in a male, 188 

 mm. in a female, and 186 mm. in the fledged young. The latter has the down 

 partly remaining on the belly, and on a patch on either side of the lower back, in 

 which places the fluffy downs sit on the tips of the feathers in such a manner that 

 each ramus of the feather is continued into a soft »plumule»-like part. 



A young with the length of the wing amounting to 170 mm. has almost the 

 whole body surrounded by down on top of the feathers. 



The colour of the young in its first plumage is almost identical with that of 

 the adult bird, although the latter may be a little darker. The down is grey above 

 and whitish beneath. 



The down of not yet hatched youngs is dark, almost black as well above 

 as beneath. 



The size of the eggs is somewhat variable. The following measurements prove 

 this: axis 49,5 mm.; diameter 34,3 mm. 

 » 51 34 



» 45 » » 33,5 » 



They are plain white, without gloss when washed, but in the nest they are much 

 soiled. The surface is fairly smooth. 



Mr. Sörlesg has made the following interesting observations on this bird and 

 its nesting habits: 



»On the open sea Prion is seen in enormous quantities. Here they fly round 

 above the schools of whales and procure their food. The nest is situated rather deep 

 into the ground under tussock-hills and similar formations. It consists only of a 

 hollow at the end of the burrow without any bedding. The burrow resembles that 



