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XXII. On the Impregnation q/'Dischidla. By the /a^e William Griffith, Esq., 

 F.L.S. 8fc. 8fc. Communicated hy R. Brown, Esq., V.P.L.S. Sfc. 8fc. 



Read March 2nd, 1847. 



1 HE following observations were made on the Dischidia Rafflesiana, Wall., 

 about the 18th of January 1835. They were confirmed by subsequent re- 

 examination about a week after that time, and, with the exception of the 

 development of the ovula, by the examination of another species, apparently 

 allied to D. hengalensis, on the 3rd of February 1835. I shall first run over 

 the changes that occur in the ovula while passing from their infant to their 

 perfect form. 



At the earliest period the ovula are mere rounded elevations on the pla- 

 centae, attached to this by broad bases (Tab. XVIII. fig. 1). The first change 

 takes place when the corolla begins to exceed the calyx in length, and merely 

 consists of a narrowing towards the base (Tab. XVIII. fig. 2). When the 

 corolla is about twice as long as the calyx, this narrowed portion has put on 

 the appearance of a funiculus. At the same time a rounded rather shallow 

 cavity appears on the upper edge of the ovule and close to the funicle. Both 

 diameters of this are nearly equal (Tab. XVIII. fig. 3). The changes now take 

 place rapidly. When the corolla is two-thirds longer than the calyx, the ovula 

 have assumed to a considerable degree their perfect form, differing chiefly in 

 size. The rounded cavity has now assumed the appearance of a deep fissure, ex- 

 tending from the base of the ovule close to the umbilical cord, along the upper 

 margin of the ovule for about one-fourth of its length. The margins of this 

 fissure appear raised : its greatest diameter is longitudinal (Tab. XVIII. fig. 4). 

 Up to this period there is no trace of a central excavation or cavity. When 

 the corolla is half-developed the ovule retains the same form, but the fissure 

 is longer and its lips more expanded. A small rather indistinct grumous-look- 

 ing mass is now visible in the central line, but towards the apex of the ovule. 



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