SIR w. jardine's notes on birds. 31 



but, on closer investigation, I found that 1 had mistaken for these cer- 

 tain muscular fibres, and some very slender vessels which have not the 

 usual structure of the windpipe. I could no where find either spiracles 

 or gills ; and I was thence led to believe that the sugar-louse breathes 

 through the whole surface of the body (ganzen oberfltiche des korpers), 

 which is everywhere clothed with shining scales, and these, under a 

 higher magnifying power, appear to be placed on a foot stalk, and 

 marked with longish lines (figs. 1, 2, 4). Now why should not these be 

 the valves of the spiracles? I cannot, however, prove the truth of this 

 conjecture, except from the apparent absence of any other apparatus 

 for breathing. Yet it is proved by the experiment of Sorg (Disquis. 

 Physiol, circa Respir. Insect et Verm. p. 109), that, without some 

 organ of breathing, they could not consume so much oxygen, and appear 

 so sensibly distressed by the presence of hydrogen. 



The nervous system of the sugar- louse consists of the brain* ( 1 , fig. 3), 

 and eleven nerve-knots (2-12), of which the three first (2-4)_and the 

 last (12), are precisely the size of the brain, while the others (-5-11) 

 are very small. The brain differs from the nerve-knots in nothing 

 more than in giving origin to the nerves of the eyes (o, o), which I have 

 been able to see distinctly, With respect to the higher functions of 

 the brain all these animals must rank in a very low scale. 



SIR W. JARDINE'S NOTES ON BIRDS.f 



There can be no question that Sir W. Jardine stands in a high rank 

 among our living British Naturalists, a rank which the Notes before us, 

 as well as those he has given to " White's Selborne," would entitle us 

 to claim for him, independently of what he has done in his splendid 

 work on British Birds. With the exception of one thing also, which 

 we shall not now stop to discuss, he can write with an elegance and 

 spirit, very superior to the meagre and uninteresting matter so frequently 

 met with in works on this subject. His Life of Wilson accordingly, is 

 admirable : and we regret much that our plan, and still more our 

 limits, forbid us to touch this portion of the work, even in a sketch. 



* See Alphabet of Insects, pp. 75 — 81. — Edit. 



t American Ornithology ; or the Natural History of the Birds of the United States, 

 by Alexander Wilson ; with a Continuation, by C. L. Buonaparte, Prince of Musig- 

 nano. The Illustrative Notes and Life of Wilson, by Sir W. Jardine, Bart., &c. 

 3 vols. 8vo., Edinburgh and London, 1832. 



