225 
Thiselton-Dyer . —Morphological Notes. 
the bilobed seed. Sir William Hooker figures in the Botanical Magazine 
(tab. 2737, fig. i) a transverse section of an ovary which clearly points to a 
normal tricarpellary structure. 
The stone, or nut as it is sometimes called, is, as is well known, deeply 
bilobed. As shown in Plate XIX the outline of the putamen in a longitudinal 
section is roughly that of an exaggerated dumb-bell. The cavities of the 
two lobes communicate in the middle. The upper parts of the lobes are 
separated by an open sinus, but the lower are more or less united, and if a 
cross section be made at this point, the nut would show, as in one of 
Sonnerat’s figures, a bilocular structure. 
Another point which has not been ascertained is the number of ovules 
in each ovarian cell. Analogy and such evidence as is available suggest there 
being only one. The ‘nut * therefore, if developed from one carpel, would be 
only one-seeded. W. B. Hemsley, in the Catalogue to the North Gallery 
(p. 74), refers to ‘ the two-lobed nut, which usually contains only one seed \ 
But I am not aware of any proof of its ever containing more. It seems 
probable that the bilobed form of the nut has suggested that it might 
consist of two coalescing carpels, but there is no evidence for this. 
Juglans affords a familiar instance of ingrowths from the pericarp into the 
seed cavity. The purpose of such spurious dissepiments, especially when they 
intrude on the developing seed and modify its form, is difficult to account 
for. The separation of the cavities at the base of the seed of Lodoicea is 
apparently due to such an ingrowth. But this can only be ascertained by 
following the development. The free lobes themselves are only lateral 
inflations in order to provide space for the enormous endosperm. They are 
much more distended on the dorsal than on the ventral surface, which is 
somewhat flattened ; this produces the corresponding difference in the two 
surfaces of the fruit which has already been mentioned. In this case, which 
seems the most usual, the fruit contains only one nut and one seed. 
The Ge 7 iera Plantarum describes the fruit as ‘ 1- v. imperfecte 2-3- 
locularis ’. The latter condition can be only due to the more or less com¬ 
plete development of one or both of the other carpels. 
The endosperm is voluminous. According to the Genera Plantarum it is 
hollow, ‘ late cavo.’ My recollection of a specimen examined at Kew, though 
unfortunately I made no note at the time, is that it was solid. The account 
given by Sir William Hooker seems to confirm this. He says : ‘ The cavity 
is filled by the almond , which is very hard, white, and corneous, so that it 
may be rasped with a file, but is with difficulty cut with a knife.’ I can 
only conjecture that this must have been described from an old and 
desiccated nut. A fresh one which afforded Dr. Walter Gardiner material 
for a study of the histology of the endosperm must have been immature, for 
sections were easily cut with a razor, and the consistence was not much 
harder than that of a turnip. 
Q 
