292 ON SEEDLINGS 



dons inflexed ; while those of Janusia are fleshy and curved, 

 but are somewhat exceptional in having the inner one uncinate 

 at the tip. A fourth type has the cotyledons circinate, those 

 of Byrsonima and Dinemandra being linear and semiterete. 

 Pterandra is very exceptional in the Order in having the seed- 

 leaves flattened and convolute, while the inner one is longer and 

 rolled up in a spiral of many coils. 



The seeds are often large, and as they contain no endosperm, 

 the embryos in numerous cases are thick and fleshy. The 

 gyncecium in Hiptage Madablota consists of three carpels, and 

 is three-celled, with one ovule in each cell. The ovule is cam- 

 pylotropous or semi-anatropous, suspended from the middle by 

 a broad obliquely attached funicle. The fruit is samaroid with 

 three strong wings diverging from its upper edges, and when 

 mature splits into three pieces. The seed is transversely and 

 broadly oblong-reniform, large, and conforming to the seed- 

 cavity of the samara. The embryo is large, slightly curved, 

 thick, fleshy, pale yellow or white, and the cotyledons are un- 

 equal, plano-convex, with the smaller one uppermost, lying in 

 the sinus of the curve ; both lie in the narrow plane of the 

 seed, with their edges to the ventral suture of the carpel. The 

 radicle is superior, and so short as to be hardly noticeable, 

 just serving to unite the cotyledons. Other genera agreeing 

 with Hiptage in having fleshy seed-leaves are Acmanthera, 

 Acridocarpus, Brachypterys, Stigmaphyllon, Tetrapterys, and 

 Hirsea. 



Hiptage Madablota may be again referred to as a type 

 having unequal cotyledons. Others agreeing with it in 

 this respect are Burdachia, Dicella, Thryallis, Galphimia, 

 Heteropterys, Stigmaphyllon, Tetrapterys, and Pterandra. 

 This inequality is sometimes carried so far that one of the 

 cotyledons becomes quite minute, as in Hirasa. The embryo of 

 Brachypterys appears undivided, but one cotyledon becomes 

 aborted, and the other thick, and hooked at the apex. Ac- 

 cording to Grisebach l this is what takes place in Glandonia, 

 a genus containing a single species from northern Brazil. 

 According to other authorities 2 the cotyledons have become 



1 Griseb. in Mart. Fl. Bras. Malpigh. p. 23. 

 * Gen. Plant, i. 252. 



