500 CANAL IN THE SPINAL MARROW. 



with (mother on the division of the stem of plants, frith* 

 out which i cannot well explain the discoveries I think 

 1 have made with respect to the motion and general fornif 

 ation of plants, or the eifect that grafting and budding of 

 every kind have on trees; a study which is now occupying 

 every moment of my time, and from which 1 hope to draw 

 many useful hints. 



The mistake made by my directing my letters to be sent 

 to Mr. I. has led you into an errour. It is Mrs. Agnes Ib^ 

 betson, who has the honour of being your correspondent. 

 Dear Sir, 



Your obliged servant, 

 Bcttcvcv, June 8. A. IBBETSON. 



Explanation of the Figures. 



Ixpfcrration Plate VII, figs. 1, 2, 3, 4. Commencement of the growth 

 *' ie ^ a e * of leaves, exhibited in different stages. a,a,et,«, the midrib, 

 by by by the young vessels appearing like cotton, c, c, the 

 spiral nerves. «?, the smaller vessels crossing each other. 



Fig. 4. The formation of the pabulum* e, e, the fine 

 vessels growing up each side of the midrib. f y the pabu- 

 lum. x 



Fig. 5. Leaf-bud of the limetree. 



Fig. 6. Leaf-bud of the horse chestnut about January. 



Figs. 7, 8, and, 9, with some others, belong to two papers, 

 vrhieh will appear next month. 



XVT. 



A Letter on a Canal in the Medulla Spinalis of some Quadru- 

 peds. In a Letter from Mr. William Sewell, to Eve- 

 rard Home, Esq. E.R.S,* 



SIR, 



Canal in the A.CCORDTNG to your request, I send you an account 

 sninalmarrow jj tne f ac ts I have ascertained, respecting a canal I disco- 



-* rhilos. Trans, for 1809, Part I. p. 146. 



vered 



