OF THE DIPTEROCARPACER. 113 
the latter intrudes the lignified placenta, to which the remains 
of the dissepiments are attached. At first sight placenta and 
dissepiments appear attached to the inside of a membranous 
cup, which is attached to the endocarp at the base of the 
fruit (fig. 26). But on closer examination a furrow or fold is 
seen in the side of the cup mentioned, and it is found that 
the placenta is enveloped by the remains of the testa, and that 
the membranous cup is the lower portion of the testa of the one 
seed which has arrived at maturity, the upper portion having 
been torn. The testa in this and other species of Balanocarpus 
is not attached to the embryo, but loosely envelops it, and is so 
thin that it tears when the seed is taken out from the fruit. It 
gives me great pleasure to state that Dr. Stapf, of the Royal 
Herbarium, Kew, to whom I showed this peculiar conformation 
of the seed, drew my attention to the furrow in the basal cup, 
which I had previously overlooked. In fig. 5 this furrow is 
not clearly indicated on the right-hand side of the figure. 
The peculiar feature here is, that at the base of the fruit the 
testa seems to be attached to the inner surface of the pericarp. 
13. BALANOCARPUS ACUMINATUS, Brandis.—Richetia acumi- 
nata, Heim in Bull. Soc. Linn. Paris, ii. (1891) 979. 
Borneo (Beccari, n. 2942). 
Tertiary nerves reticulate, inner segments of fruiting-calyx a 
little longer than the outer. 
14. B. seu xnocanPvus, Heim, Recherches, p. 77. 
Borneo (Beccari, 3021). —[ Not seen.] 
Near Balanocarpus, Heim places a genus established by him 
upon specimens from Borneo (Beccari, 3314) in fruit only, and 
this fruit without perfect seed— Pierrea pachycarpa, Heim, in 
Bull. Soc. Linn. de Paris, 1891, p. 958; Recherches, p. 78. The 
fruit is upon a very thick receptacle, enclosed by 5 equal thick- 
ened calyx-segments which are nearly as long as the fruit. The 
pericarp apparently splits into three segments, and while it is 
thin near the base, is much thickened, woody, in its upper conical 
part. Regarding the anatomical structure, Heim states that 
there are two resin-ducts at the base of the internodium, but 
a larger number higher up, as many as 12 in the lower third, 
which number again diminishes to 5 in the middle of the inter- 
Three leaf-traces enter the petiole, viz. the apical 
I 
nodium. 
LINN. JOURN.—BOTANY, YOL. XXXI. 
