SCHOMBURGK’S GUIANA PLANTS. 135 
Gardner’s n. 361 from the Organ Mountains, Martius’s 
Acacia fruticosa, and two other species in my herbarium, have 
the flowers, inflorescence, and in most respects the habit of 
Plathymenia, Adenanthera and Stryphnodendron ; the glands of 
the anthers are however small and often so fugitive that the 
bud must be opened carefully to find them still adhering, and 
the pod is that of an Acacia. The leaflets, as in the three 
above-mentioned genera, are broad and blunt, but the petioles 
appear to be constantly prickly, To this group I have 
given the generic name of Piptadenia. 
Another set of near a dozen Brazilian species agree with 
Piptadenia in flowers and inflorescence, but the leaflets are 
Very numerous, small, narrow, and pointed, which gives to 
the specimens the appearance of the true Acacias, or of the 
spicate-flowered Mimosas. I have seen the pod of but one 
Species, and that isnot ripe. If, as it appears to do, it agrees 
with that of the other Piptadenie, this group would form a 
section of that genus. 
I have about eight species which I should refer to StrypA- 
nodendron of Martius. Amongst these, Gardner's n. 364 
from the Organ Mountains is S. polyphyllum, Mart.; his n. 
986 from Pernambuco, is a new species closely allied to it ; 
Blanchet’s 2899 from the Sierra Acurua (to which belongs 
also probably his n. 2701 from the Serra Jacobina), is re- 
markable from the pod being flatter and much contracted 
between the seeds, but it appears to be a true Stryphnoden- 
dron. De Candolle’s Acacia psilostachya, which I received 
from Cayenne, seems also to be referrible to this genus. - 
Mimosa Guianensis, Aubl. Pl. Gen. II. p. 938 t. 351, has from 
that figure all the appearance of a Stryphnodendron, but the 
fruit is described as thin, membranous and bivalved, which . 
would place it in Piptadenia. ‘There are however so many 
instances where Aublet is known to have mismatched fruits 
— this case, more especially as he gathered the flowering and — 
fruit-bearing specimens at several months’ interval. ; ju 
.. The East Indian genera, Adenanthera and Prout ; 
and flowers, that there is no certainty of his correctness in — 
