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catum, 5-loculare, loculis bi-ovulatis; ovula ex apice 
anguli interni suspensa. Stylus brevis, 5-gonus, apice 
acutus, vix pilis germinis longior. Fructus villosus, 
capsularis, subulatus, 5-angulatus, indehiscens; carpellis 
dorso infra medium calcare subulato longo deflexo; en- 
docarpium a sarcocarpio non solubile marginibus in- 
troflexis a placenta centrali 5-angulari demum solutis. 
Semen in fructu solitarium, ceeteris (an semper ?) abortien- 
tibus, pendulum, compressum. Albumen tenue carnosum. 
Embryo rectus: cotyledones plane, foliacez, ovales; 
radicula cotyledonibus brevior supera.—Frutex pro- 
cumbens ? ramosus ; rami nodosi, striati, grisei, spinosi : 
spinis (ramis abortivis) ex nodis solitariis ad basin fere 
4-partitis ; segmentis subulatis, rectis, validis, subequali- 
bus, horizontaliter patentibus, cum mucronula brevi (seg- 
mento quinto abortivo?) supra inter bases. Folia ad 
gemmos infra spinas fasciculata impari-pinnata : foliola 
4—5-juga, oblonga, basi hinc lobata, sericeo-pubescentia, 
terminali minore, Flores inter Jolia: pedunculus brevis, 
simplex, villosus 
- (1.) P. tetracantha (Gill. mst.)—On “travesia” or un- 
cultivated plains near Los Cerrillos de San Juan, pro- 
vince of San Juan, (2000-2500 feet,) Dr. Gillies.—This 
is a very remarkable plant. The flowers, leaves, spines, 
and also branches, are all inclined to one side, and 
hence we presume the shrub to have been prostrate. It 
is difficult to judge whether the spines ought not to be 
viewed as four horizontal spines, set round on an exceed- 
ingly short abortive branch, which is terminated by a 
little point or mucro between the spines. The subulate 
fruit, each of the projecting angles, or constituent carpels 
of which is furnished with a singular spur, villous as 
well as the fruit, and bent slightly downwards, is totally 
unlike any thing else we know. Only one ovule appears 
to be perfected : the remains of the others may, however, 
be traced in the advanced fruit. The genus obviously 
comes next to Porlieria and Larrea: 
