324 Linnean Society. [March 2, 



struck in 1758, in honour of Linnseus, by order of Count Tessin, 

 Marshal of the Diet. 



Read also a paper " On the Impregnation of Dischidia." By the 

 late William Griffith. Esq., F.L.S. &c. &c. Communicated by 

 Robert Brown, Esq., V.P.L.S. 



In this paper, dated " Mergui, March 7, 1835," Mr. Griffith de- 

 tails a series of observations made in January of that year on Dis- 

 chidia Rafflesiana, Wall., and confirmed' (with the exception of those 

 relating to the development of the ovule) by the examination of an- 

 other species, apparently allied to D. Bengalensis, Colebr. 



Mr. Griffith commences by a description of the progress of the 

 ovula from their first appearance as mere rounded elevations on the 

 placenta. The first change consists in a narrowing towards the base, 

 which afterwards puts on the appearance of a funiculus, and at the 

 same time a rounded rather shallow cavity appears on the upper 

 edge of the ovulum close to the funiculus. The further changes take 

 place rapidly ; the rounded cavity assumes the appearance of a deep 

 fissure with raised margins extending from the base of the ovulum, 

 close to the funiculus, along the upper margin of the ovulum for 

 about one-fourth of its length. This fissure gradually lengthens ; 

 its lips become more expanded, and a small indistinct grumous-look- 

 ing mass becomes visible in the central line and towards the apex of 

 the ovulum, which is the first rudiment of the nucleus, or of the ca- 

 vity within which the future embryo is to be developed, and which 

 becomes subsequently more distinct, and frequently assumes a 

 rounded form. In the perfect ovule the fissure is very large, extend- 

 ing longitudinally from the base of the funiculus for about one-third 

 of the length of the convex upper margin of the ovule ; its lips are 

 gaping, and it is of considerable depth, gradually narrowing towards 

 its fundus. The grumous mass is now very distinct and the first 

 indications of an excavation around it are appreciable. When no 

 impregnation has taken place, in flowers that have passed their me- 

 ridian, the excavation is enlarged, the grumous mass is more irre- 

 gular, and it frequently appears to be broken up, the component 

 parts being irregularly grouped together. 



The partial closing of the corolla of Dischidia by the connivence 

 of its divisions, and the short hairs with which those divisions are 

 furnished internally in D. Rafflesiana, induced Mr. Griffith to regard 

 foreign agency as inapplicable in determining the escape of the pol- 

 linia from their anthers, and to believe that impregnation in any 

 given floM^er is in this genus the result of the action of its own pel- 



1 



