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- probable that they are the produce of different plants. 
Tn fact, according to the reactions we have obtained, and which are 
described later on in this paper, Natal aloes would seem to be derived from 
Aloe succotrina rather than the species to which it has hitherto been 
“There is one point to which we wish particularly to eall attention. 
When nitric acid is added to Cape aloes on a white platea reddish colour 
is produced, but this is not a colour by which Cape aloes eould be 
identified. If the two be allowed to remain in contact for some time, 
five minutes, for instance, a green colour is produced which is permanent 
for some hours. This is a reaction which we found constaut with all 
good test for Cape aloes. Seeing that this reaction is constant with all 
the specimens of Cape aloes examined, we thought an effort ought to be 
made to ascertain the species yielding this variety of aloes. It has been 
stated to be obtained from various species, viz., Aloe spicata, A. platy- 
lepis, A. plicatilis, A. ferox, A. arborescens, A. perfoliata, A. lingua- 
ormis, A. purpurascens, &e., or it has been thought to be the product 
of the mixed juices of several species or of the hybrids obtained by 
-crossing them. 
“Tt was suggested by Mr. E. M. Holmes, F.L.S., that it might be 
possible to determine this point by testing the aloes obtained from leaves 
f authentic specimens of the various species of aloe as grown at the 
Royal Gardens, Kew. 
* By the kindness of Mr. W. T. Thiselton Dyer, F.R.S., Director of 
Kew Gardens, to whom Mr. Holmes applied on our behalf, we were 
— 5 imde up this idea, The leaves of a number of different 
Species or a i 
* We were unfortunately unable to obtain a genuine specimen of Aloe 
a | 
think this is rather improbable, as it is, according to Mr. Watson 
(Assistant Curator of Kew Gardens), a comparatively rare species at the 
Cape, and the leaves are much smaller, and not so succulent as in the 
other species. 
* With several of the specimens of aloes obtained by us from plants 
grown at. Kew, a reaction was obtained which we did not find with any 
commercial specimen, viz., 1 drop of bromine water, added to a little of 
~ the powder, developed a colour varying from pale to dark purplish-red 
_ Or damson-colour. | 
. .. “We do not consider this reaction as a proof that the commercial — 
. aloes are not derived from these species, but think it possible thatthe —— 
