122 Dr. Carpenter. 



complete cells, but they do not contain honey now. The 

 material of which the cells are made are very inflammable, 

 allied to wax, if not true wax, and it is probable that the inner 

 side of the mossy dome was lined with a similar kind of 

 material by means of which the rain was kept out of the mass, 

 but I did not find any evidence of such a dome in the felted 

 mass which I removed. 



27. — One of the means whereby Forest Trees are 

 destroyed. 



By Alfred Carpenter, Esq., M.D., &c. 



[^Read ijth December, 1881.] 



Dr. Carpenter, being called upon by the President, read a 

 short paper on a peculiarity in the birch tree. It was as 

 follows : — The specimen submitted is a portion of the 

 Betula Alba, the ordinary birch tree, a tree which is very 

 common in light and sandy soils, and in all hilly countries. 

 In this specimen, which has been recently cut down, it will be 

 observed that included within the true wood is a layer of what 

 appears to be the liber of the bark, and which is in the form of a 

 paper lining. The specimen was brought to me by Mr. 

 Flaxman, the dairy inspector, as shewing how curiously a 

 sheet of paper had become impacted in and become a part of 

 the tree. It may not be an uncommon thing, but I have not 

 seen it before, neither do I find any account of a similar 

 production in any of the botanical works to which I have 

 access. It will be observed in the specimen that the abnormal 

 condition is limited to the duramen, and the very centre of the 

 wood appears to be undergoing a process of decay. The rings 

 are very indistinct, as is usual with the birch, but the paper like 

 envelope seems to take in two or three of the rings. My first 

 impression was that some abnormal state of nutrition enabled 

 the alburnum of the wood to enclose the liber or inner layer of 

 the bark and cut it off from communion with the cellular or 

 corky layers, I expected to find evidences of this by 

 examination of the tissue with the microscope. My first 

 difficulty, however, arose in finding that the tissue was formed 

 in a matted or felted plan, and not in parallel layers or lines, 

 as is the case in bark. It was not acted upon by acetic acid. 

 Boiled with nitric acid it was simply rendered more granular. 

 Boiled with acetic acid the same result followed, and not the 

 change which usually comes over lignine when so treated. A 

 portion of the tissue teazed out with the needle, and examined 

 with a one-fifth power showed a felted mass of fine fibres with 

 distinct contour, but without nuclei and none of those markings 



