380 EXPEDITION TOWARD THE NORTH POLE. 



What lias been said in regard to the mammals will apply equally well 

 to the birds, skins and skeletons being equally desirable. It is espe- 

 cially important that the fresh colors of the bill, cere, gums, eyes, and feet 

 or caruncles, or bare skin, if there be any, should be noted, as the colors 

 of these parts all change after the preparation of a specimen. 



Of birds, the smaller land species are of the greatest interest, and com- 

 plete series of them should be gathered. The northern range of the in- 

 sectivorous species should be especially inquired into. The arctic falcons 

 should be collected in all their varieties, to ascertain whether there are 

 two forms, a brown and white, distinct through life, or whether one 

 changes with age into the other. 



Inquiry should be directed to the occurrence of Bermcla Icucopsis, 

 Anser ciuercus, or other large gray geese, and the Camptokcmus Lahra- 

 dora, and'a large number of specimens, of the latter especially, should 

 be obtained. Indeed the geese and ducks generally should form sub- 

 jects of si)ecial examination. Among the Laridw the most important 

 species is the Larus rossii or Ehodostethia rosea, scarcely known in col- 

 lections. A large number of skius and of eggs will be a valuable ac- 

 quisition. Larus churneus is also worthy of being collected. The AJcidce 

 should be carefully examined for any new forms, and inquiries directed 

 in regard to the AIca impcnnis. 



Of all birds' eggs an ample store should be gathered, and the skel- 

 etons of the Arctic raptores and Xatatores generally. 



It will be a matter of much importance to ascertain what is the ex- 

 treme northern range of the continental species of birds, and whether, 

 in the highest latitudes, the European forms known to occur in Green- 

 land cross BaflSn's Bay. 



Eggs and nests of birds, in as large numbers as possible, should be 

 l)rocured, great care being taken, however, in all cases, to identify thetu 

 by the parents, which may be shot, and some portion, if not all of them, 

 preserved, if not recognized by the collector. All the eggs of one set 

 should be marlced with the same number, that they may not be sepa- 

 rated ; the parent bird, if collected, likewise receiving the same number. 

 It should also be stated, if known, how long the eggs have been set 

 upon, as incubation influeiioes very much their color; the situation of 

 the nest also is very imi)ortant. Notes on the manner of nesting, local- 

 ities selected, and other peculiarities of breeding, should be carefully 

 kept ; whether they "are polygamous, whether there are struggles be- 

 tween the males, and the manner in which the old birds feed their 

 young; and w'hether these remain helpless in the nest for a given time, 

 or whether they accompany the parents from birth. A journal of the 

 arrival and departure of the migratory species should also be kept, to 

 find out whether those which leave latest return earliest, and vice versa. 



Of fishes that are obtained, the best specimens should be photo- 

 graphed, the fresh Qolors noted, and then they should be preserved in 

 iilcohol or carbolic acid. • 



