OF SOME SAPOTACEOUS SEEDLINGS. 195 
sign of a midrib, but are penetrated by one larger median vein and two smaller divergent 
lateral ones. On the dorsal side there is a slight keel. One type of seedling (B) was 
hexarch throughout, and “ the vertical median plane of the cotyledons corresponded with 
a vascular bundle of the root.” Three double bundles pass into one cotyledon and four 
into the other, the fourth bundle arising at the node. It is a single bundle and 
resembles a foliar trace (text-figs. 5-7). 
In another type (A) the root was heptarch ; but below the node an eighth bundle 
arose and four double bundles passed into each cotyledon. Here the vertical median 
plane of the cotyledons did not correspond with a vascular bundle of the root (text- 
figs. 8, 9). 
Scarcity of material prevents any generalization as to which is the prevailing type in 
the species. 
In an unnamed species of Palaquium irom China the stele is hexarch throughout and 
conforms with Dangeard’s axiom. ‘Three double bundles pass to each cotyledon and 
fork and anastomose in it. The external features of this species are, on the whole, 
similar to those of P. petiolare, but the cotyledons are rather less thick. 
Achras Sapota agrees more closely with the Payena .Leerii type than any other species 
examined; but the embryo in the ripe seed is much less mature. No latex tissue and 
nolignifieation were apparent. A seedling measuring about 18 mm. from node to root- 
apex showed no swollen zone in the hypocotyl, no lignified parenchyma, and no 
secondary thickening. It was much younger than any specimen of Payena .Leerii 
which I possessed. It had no foliar traces. The isolation of the protoxylem from the 
metaxylem groups on each side of it is very striking. 
Bassia latifolia (Illipe latifolia) and Bassia longifolia (Illipe Malabrorum) agree in 
the seedling with the type on the whole, and have a zone of thickening in the hypocotyl. 
Thad no seeds of these two species. 
Mimusops Elengi agrees on the whole with Payena Leerii. The ripe seed contains an 
embryo much less advanced than that of the type—having neither latex nor vascular 
tissue differentiated. The procambial strands indicate a stele like that of P. Leerii, 
and this is realised in the seedling. A zone of thickening is present here in the 
hypocotyl at about half the length from node to root-apex (Pl. 26. fig. 18). 
The behaviour of the double bundles as they pass to the cotyledons here and in 
Chrysophyllum Cainito differs slightly from the type and shows that the feature is not 
* constant one, and also indicates the independence of the halves of the said bundles. 
d do not. bend out together, but whereas in JM. Elengi the inner halves precede the 
ones, the reverse is the case with Chrysophyllum Cainito. Also in a specimen of 
a showing signs of injury the two halves of a double bundle ene continued 
i. P tay as separate groups, and never united at the corner of the stele. ane 
w "ume xylem group at the node, between the groups destined for one pi yis did 
i E for by observing that 5 per cent. of the seedlings of this species seas 
vertically over a cotyledon. No other foliar traces were to be seen at this 
` About 6 per cent, of the seedlings of this species have bifid coty ledons. : 
-MUSODS Kauki has a seed with endosperm and thin cotyledons. This species 
