404- 



An Account of an Appendix to the small Intestines of Birds. By James 

 Macartney, Esq. F.R.S. Read March 21, 1811. [Phil. Trans. 

 1811,^. 257.] 



Although almost every author who has written upon the incubation 

 of the egg has observed the direct communication between the yolk- 

 bag and the small intestines of the chick, and although some of them 

 have observed that this duct remains in the form of a small caecum 

 during life, it appears to have escaped the notice of any one, that in 

 some species of birds this part is of considerable size, and possesses 

 a structure pecuh'ar to itself. 



It was in the snipe that Mr. Macartney first observed its magni- 

 tude to exceed that of the caeca of the great intestines ; and he has 

 since found that in the woodcock and curlew it is proportionally 

 large. In the black coot also, it is long, but slender, like the rest 

 of the intestines in that bird. 



In the swan and goose it does not bear the same proportion as in 

 the preceding, though somewhat larger than in the generality of 

 birds. 



This caecum consists always of two tunics, corresponding to the 

 peritoneal and villous coats of the intestinal canal in general, but 

 without any appearance of intervening muscle. Its interior surface 

 is composed of small cells, like the 1 assemblage of mucous follicles, 

 found in various parts of the alimentary canal. The matter contained 

 in this appendix has never been found the same, as in the adjoining 

 intestines, but it has been always filled with a mucous fluid, which it 

 seems to secrete. 



This appendix, in most birds, retains evidence of its origin ; for 

 the remnant of the yolk-bag is commonly found adhering to its ex- 

 tremity, and still communicates freely with it, especially in the Acci- 

 pitres, and in the passerine tribe. In the nightingale Mr. Macartney 

 observes, the duct is scarcely visible ; but the yolk-bag remains du- 

 ring life as a sac, the size of a large pea, communicating with the 

 intestine. 



The preceding facts, says the author, are curious instances of an 

 organ of foetal life retained in the full-grown bird, for the exercise of 

 a particular function. 



An Account of a vegetable Wax from Brazil. By William Thomas 

 Brande, Esq. F.R.S. Read May 9, 1811. [Phil. Trans. 1811, 

 p. 261.] 



The substance here examined by Mr. Brande, had been sent to 

 Lord Grenville from Rio de Janeiro, and by him given to Sir Joseph 

 Banks, in the hope that when its properties were investigated, it 

 might be found to answer the purposes of bees' wax, and become a 

 valuable article of commerce between Brazil and this country. 



It is said to be the produce of a tree of slow growth, called by the 

 natives Carnauba, and growing in the most northerly part of the 



