268 THE BOTANICAL LABOURS OF 
This is an anatomical description of the structure of the stinging 
hairs of this Brazilian Nettle, and of the mechanism by which the 
author believes that the acrid juice is injected into the wound. He 
believes that the inflected globular end of the hollow stinging hair is 
broken off as it penetrates the skin, thus opening an orifice for the 
discharge of the acrid liquor always contained in the vesicular base of 
the hair. The plate gives highly magnified figures illustrative of the 
anatomical details. 
5. Notes illustrative of the history of the Forest-trees of Brazil, espe- 
cially of the province of Rio de Janeiro ; by Dr. Allemáo. 
After some general observations, this paper contains a list of the ` 
most valuable of the trees which the author has had more or less op- 
portunity of studying, arranged in their Natural Orders under their 
native names, with the addition of the scientific names of such as he 
has been enabled to determine, further details being reserved for fu- 
ture communications. The list contains ninety-eight trees, of which 
thirty-five belong to Leguminose, six each to the Lecythidee and Lau- 
rine@, five to each of the Bignoniacea, Sapotacee, and Meliacee, and 
the remainder dispersed through sixteen other Orders. Of this num- 
ber seventy at least are stated to supply good building timber, the 
remainder being generally classed among madeiras brancas, or white 
woods. Dr. Allem&o observes however upon the extreme difficulty of 
classing the woods according to their qualities, from the vague use 
made of such designations as páo bom and qo átóa, etc., which may be 
rendered as useful and useless woods: many, he says, which were for- 
merly neglected as too common and useless, are now turned to account 
and gaining in estimation. : 
. Among the observations which follow on the local names of trees, 
we see the explanation of the specific name of Zegalis, not unfrequently 
taken up by Velloso in the“ Flora Fluminensis.’ The term of legal or 
royal trees or woods, is commonly applied in Brazil to those trees 
which, being reserved for naval constructions, individuals were by law 
prohibited from felling. 
Looking over the list for such names of woods as are more or less 
familiar to us, I was struck with that of Jacaranda, generally given as 
the Brazilian name of our cabinet-makers’ rosewood (the palissandre of 
the French), which is here applied exclusively to several species of 
Macherium, thus again unsettling our ideas as to the tree which sup- 
