tion 2560 which indicates that he himself considered these 
two collections as representing the same concept : 
2560, Siphonia discolor sp. n. gap6. Sm. milky tree 20 ft. Petioles 
54 in. Lts. 643, subov.-ellipt. with abrubt subobt. apic. ven. wsh. 
and pubt. Pans. subpubt. Fl. very p. y. pubt., segm. acum. ef, Barra 
[Mandos] Siphonia 1171. 
If we analyze, point for point, Bentham’s description, 
we find that the leaflets, with their short petiolules, dif- 
ference in color of the two surfaces, presence of hair on 
the under surface and small glands, possess characters 
which one finds to be common to the two concepts which 
Spruce 1171 and 2560 represent. Indeed, vegetatively, 
and to a much lesser extent florally, ALevea Benthamiana 
often strikingly resembles H. Spruceana, a similarity 
which doubtlessly underlay Spruce’s as well as Ben- 
tham’s confusion of the two concepts as one. The pani- 
cles are tomentose in both collections, albeit a distinct 
color difference may be noted; and the floral stalk in 
both is rather short. Bentham continues by stating 
‘“‘calycibus obtusis,’’ probably meaning by the term 
‘‘calycibus’’ buds or the closed calyx, in which case it is 
obvious that he is describing Spruce 11771 and not 2560, 
for in 2560, the buds, as described by Mueller, are ‘‘lon- 
gius acuminatis’’ and the calyx lobes “‘longe acumina- 
tis.’’ Hevea discolor was described as having from seven 
to ten anthers disposed in two whorls, a character which 
might refer either to H. Spruceana or to H. Bentham- 
lana. 
Following the technical Latin description, Bentham’s 
English discussion provides additional characters of im- 
portance. ‘The mode of branching which is described can 
be seen in individuals of both Hevea Spruceana and Hi. 
Benthamiana, but my experience leads me to associate 
it more frequently with the former than with the latter. 
The latex is said to yield an elastic rubber. This is an 
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