IIAltDWICKE'S SCIENCE-GOSSIP. 



109 



three or four years older, think it a new species, 

 and crown Lis efforts by a second baptism under 

 another appellation {e.g., Lams marinus). The 

 principal characteristic features of the sea-bird 

 known under the name of the Arctic Gull {Lestris 

 or Stercorarius parasiticus), are as follows ;— Front 

 (including the throat, the region below the eyes, 

 the neck, breast, belly, and abdomen) is of a pure 

 white colour; the head is crowned by a blackish- 

 brown hood; the feet are deep black; and the 

 lower coverts of the tail, the back, wings, and 

 caudal feathers (two of which extend much beyond 

 the others), are of a deep ashy-brown colour. The 

 total length of the bird is about Hi inches. 



Several other species of this genus, e.g., L. 

 Jtichardsouii, L. pomarinus, L. Buffonii, &c, are 

 likewise distinguished by the practical demonstra- 

 tion of piratical propensities. Want of space, 

 however, and the fact of their being distinguished 

 from the foregoing by comparatively unimportant 

 peculiarities, will prohibit my entering into a minute 

 examination of them. It may be better for me to 

 endeavour to deduce a few general propositions 

 from the facts above stated. 



1. In the first place, it may be observed that a 

 very little contemplation of the habits, method of 

 living, and physiological structure of any of these 

 birds {e.g., Lams marinus), convinces us that their 

 corporeal constitution is eminently adapted to the 

 birth and maintenance of a vast amount of animal 

 force. The immense expenditure of physical power 

 involved in the demonstration of their pugnacious 

 inclinations, in their rapid and continuous flight, 

 and generally in their restless, insatiable method of 

 comporting themselves, must assuredly be somehow 

 or other compensated for. Now it seems to be a 

 fact clearly recognized by physiologists, that the 

 blood constitutes the great storehouse of animal 

 activity. It circulates extensively through the 

 nervous centres, thereby furnishing them with an 

 adequate opportunity of performing their extra- 

 ordinary function of converting it into a corre- 

 sponding amount of the nervous force that ministers 

 to the actions of the muscular apparatus, &c. The 

 point which I wish to draw special attention to is, 

 that this energy or power is not accumulated and 

 laid up in the centres for future expenditure, but 

 is evolved out of the blood, according as it is 

 immediately required for service. Hence it follows 

 that if the animal is to be preserved in a healthy 

 and fresh condition, its blood must be thoroughly 

 adequate to meet all demands upon it, however 

 exorbitant these may be. But in order to the ac- 

 complishment of this effect, it is indispensable that 

 the blood should be well charged with fibrin and 

 red globules. The wild Indian of the prairie, who 

 subsists on nothing but animal food, presents an 

 illustrative specimen of powerful animal energy in 

 conjunction with a savageness and ferocity of dis- 



position. Iu order, however, to the maintenance 

 of this highly animalized condition of the blood, an 

 extensive digestive and assimilative power is abso- 

 lutely necessary. 



2. Hence we may be justified in concluding that 

 the members of the genera Lams, Lestris, &c, are 

 distinguished by the possession of thoroughly 

 adequate and effective masticatory and digestive 

 organs. Birds, it is well known, possess three 

 stomachs ; viz., the crop, furnished with mucous 

 and salivary glands ; the ventrieuhis succenturiatus, 

 provided with glandular bodies which secrete gas- 

 tric juice; and the gizzard. In the predaceous 

 birds it has been observed that this last is scarcely, 

 if at all, developed. Hence we may presume that 

 the second stomach is especially well developed in 

 the species of sea-bird now under review. 



3. The powerful beak and claws operating in 

 conjunction with the muscular strength, and the 

 total destitution of diving apparatus, combine to 

 render our birds essentially of a piratical nature. 

 Experiencing keenly the cravings of appetite, and 

 totally unable to satiate it by the ordinary method 

 of diving, they determine to utilize the savage 

 brute force which they feel themselves indubitably 

 possessed of. A fresh fish just caught, exhibited 

 in the jaws of some of their more gifted neighbours, 

 proves rather too strongly tempting for our friend, 

 and he scruples not to pouuee down upon it, and, 

 supported by his great physical strength, he gene- 

 rally manages to carry off the prize in triumph. 



I have endeavoured above to solicit attention to 

 a rather extraordinary proceeding by way of gaining 

 bodily sustenance practised by a highly interesting 

 genus of the order Natatores. In order, however, 

 that a thorough elucidation of the bearings and 

 importance of my subject may be furnished, it is 

 necessary to distinguish the phenomenon now 

 indicated from sundry others of an analogous 

 character, which sometimes occur amongst the 

 Mammalia. Lions, tigers, bears, &c, may at times 

 by reason of their overwhelming muscular force 

 seize and appropriate the edible matter which some 

 of their weaker brethren had just commenced to 

 enjoy ; but at the same time (unlike the Jager 

 Gulls) they are eminently capable of directly cap- 

 turing it for themselves. 



In conclusion, I cannot refrain from expressing 

 my sentiments relative to the mental elevation and 

 supreme pleasure engendered by a study of the 

 Natatorial order of birds. Intimately associated 

 with that element of Nature whose vast extent and 

 power have ever struck men with astonishment and 

 terror, the study and observation of these birds 

 must inevitably tincture the mind with wholesome 

 influences. The broad ocean, the azure or cloudy 

 sky, the rugged cliffs, and gigantic precipices, 

 furnish a scries of spectacular effects whose in- 

 fluence upon the mind has always tended to cngen- 



