CYCADACE^E 



557 



ledons are subterranean, 

 and remain in the seed till 

 the endosperm is absorbed, 

 when they decay. Another 

 peculiarity is that the plu- 

 mule consists of a mass of 

 stout, fleshy scales re- 

 sembling a resting or winter 

 bud, which emerges from 

 the fissure at the base of 

 the cotyledons during ger- 

 mination. A solitary per- 

 fect leaf is soon after de- 

 veloped from the centre 

 of the bud as seen in Zamia 

 integrifolia. This leaf con- 

 sists of two pairs of leaflets, 

 crowded together at the 

 apex of the petiole; the 

 terminal pair is much the 

 smaller, and all have 

 numerous, longitudinal, 

 parallel nerves. 



The seed of Cycas Bed- 

 domei (fig. 679) is globose- 

 oblong, and the bud formed 

 by the plumule is rather 

 small, consisting of one or 

 two scales. The method of 

 germination corresponds 

 to that of Zamia integri- 

 folia. The primary perfect 

 leaf is pinnate with eleven 

 to nineteen linear, entire 

 leaflets having a distinct 

 midrib only. Dioon spinu- 

 losum has a comparatively 

 large, oblong seed and a 

 large bud of four scales. 

 The first leaf is finely pec- 



FIG. 679. Cycas Beddomei. 

 A, first leaf; B, second 

 leaf; C, C, petioles of 

 cotyledons; S,seed. Nat. 

 size. 



