574 TRANSACTIONS AND PROCEEDINGS OF THE [Sess. lvu. 



their whole length either closely applied to them or pro- 

 jecting to a greater or less extent, especially at the lower 

 end. In colour the seed is dark greenish brown with a 

 slightly yellow tint, and its surface is smooth and shining. 

 The hilum is small, elliptical, and situated in the hollow 

 between the apcK of the radicle and that of the cotyledons. 

 It is, however, almost entirely concealed by the aril, which 

 is of a bright yellow colour, narrowly horse-shoe-like in 

 shape, and so placed that the open end lies just immediately 

 below the apex of tlie radicle. 



According to mymeasnrements the average size of the 

 seeds is 2 "5 mm. long x 2 mm. broad x I'o mm. thick, 

 while Harz (in.) mentions 3 mm. x 2T) mm. X I'S mm. 

 for the corresponding dimensions, so that the relations- 

 existing between these three dimensions appear to be 

 fairly constant, the seeds observed by Harz being merely 

 somewhat larger than those which I was able to obtain. 



Cotyledons. — The cotyledons are epigeal, and generally 

 lie expanded horizontally at no great distance above the 

 surface of the- soil. They are small, thick, bluntly elliptical, 

 quite symmetrical about their median plane, and nearly 

 twice as long as broad. They vary in length and breadth 

 between rather wide limits, but the approximate size of 

 full grown cotyledons may be expressed by the nnmbers 

 7-9 mm. long x 4-5 mm. broad. Sir J. Lubbock (v.) 

 mentions 8 mm. to l"! cm. X 4-6 mm. as the approximate 

 size, while Buchenau gives 8 mm. X 5 mm. The npper 

 surface is smooth, somewhat shining and dark green, while 

 the under side is distinctly paler in colour. They are 

 quite sessile, being attaclied to the axis by a sheathing base, 

 which is, however, much narrower than the lamina, and 

 does not unite laterally with the corresponding part of the 

 opposite cotyledon to form a closed tube surrounding the 

 plumule, though both sheaths are nearly vertical and their 

 edges are in contact on each side of the bud but not 

 united. Tlie fold, du(^ to this sheathing base, gives to 

 the narrow part of tlie cotyledonary lamina near it 

 the appearance of being concave on its upper, and convex 

 on its under surface, and is besides continued up into the 

 body of the cotyledon, as it bends outwards to assume the 

 horizontal position, and is there represented by a shallow 



