48 



DE. THOMSON ON THE STUUCTUEE 



In 1826, Bluine*, without noticing Grrertner's description, 

 ascribes to Barringtonia an exalbuminous seed, with a rugose un- 

 divided or pseudomonocotyledonous embryo. DeCandollef in 

 1828 adopted the same view, but his description of the seed seems 

 derived chiefly if not entirely from Blume. 



The genus Careya was published for the first time by E-oxburgh 

 in 1819 in the third volume of the ' Coromandel Plants.' As the 

 library of the Calcutta Grarden does not contain a complete copy 

 of this work, I have not at present access to Eoxburgh's figure ; 

 but as the letter-press does not refer to the structure of the seed, 

 it is probably not represented in the^^late. 



The earliest published account of the seed of Careya is that of 

 Buchanan Hamilton;]:, in his commentary on the ' Hortus Malaha- 

 ricus ' of Eheede, which appeared in 1827. He describes it as un- 

 doubtedly albuminous, with a straight terete central embryo, sub- 

 acute at both ends, and as long as the albumen. 



The second volume of Roxburgh's ' Flora Indica,' published in 

 1832, contains a detailed account of that botanist's observations 

 on the seeds of both genera. In Barringtonia^ he describes a 

 copious albumen, with a simple embryo (without cotyledons) of 

 the same length situated in its axis. He adds, however, several 

 details, which seem to show that he considered the structure ob- 

 scure and anomalous. In particular he tells us that the embryo 

 forms the ligneous centre of the shoots, or, as he says a little lower 

 down, the wood and pith, while the perisperm furnishes the cortical 

 part and the leaves. 



The seed of Carey a\\ is described almost in the same terms as 

 that of Barringtonia, — with a simple embryo as long as the copious 

 albumen ; and it is again stated that the embryo furnishes the 

 centre or ligneous part, and the perisperm the cortical part of the 

 young plant. It is added that the radicle issues from the small 

 end of the seed close to the umbilicus, and the scaly plumule from 

 the opposite end, a structure identical with that indicated as exist- 

 ing in Barringtonia, in which the solitary seed is pendulous, and 

 the root is developed from the apex of the fruit ; or in modern 

 botanical terms, the radicle is next the hilum and the seed ana- 

 tropous. 



In 1834 Wight and Arnott^ describe the seeds of both genera 

 as exalbuminous, with the large embryo not separable into cotyle- 

 dons and radicle, but formed of two concentric homogeneous com- 



* Bijd.. 1096. t Prodr. iii. 288. % Linn. Trans, xv. 96. 



§ Fl. Ind. ii. 635. |1 Fl. Ind. ii. 638. «![ Prodr. Fl. Ind. p. 334. 



i 



