1. CYCADACEM. [1. Cycas. 



DIVISION— GYMNOSPERMiE. 



(See Introduction. This Division and the Pteridophyta should 

 logically be placed before the Dicotyledons, which were dealt with 

 first as being in our area the most important.) 



FAM. 1. CYCADACEM. 



Shrubs or small trees, with a tliick simple (rarely forking) stem and 

 terminal crown of leaves, or stemless with leaves arising from a 

 tuberous simple or branched rootstock. Leaves in alternate series 

 of short coriaceous scales and of palm-like pinnate (rarely 2-3-pin- 

 nate) leaves with membranous or coriaceous leaflets. Flowers 

 dioecious ; males in one or more terminal cones formed of numerous 

 fleshy flat or variously peltate scales bearing on their underside 

 crowded 1 -celled anthers ; females of flat carpellary leaves (carpo- 

 phylls) crowded round the apex of the stem (in Cycas) or of flat or 

 thickened variously peltate scales arranged in cones. Ovules large, 

 sessile, orthotropous, either numerous and erect in notches on either 

 margin of the carpophyll or solitary and inverted on either side of the 

 peltate scales. Seeds large, drupaceous, with more or less fleshy 

 external and crustaceous or bony internal coat. x\lbumen copious 

 with one or more embrj'^o sacs. Embryo usually one by abortion, 

 slender, radicle superior attached to the crumpled suspensory cord. 

 Cotyledons 2. 



1. CYCAS, L. 



Shrubs or trees with a simple or rarely branched cylindric trunk 

 clothed with the woody bases of the petioles. Leaves in terminal 

 crowns, linear-oblong, pinnate, leaflets linear entire, 1 -nerved, in- 

 volute in vernation, lower often reduced to spines. Male cones 

 apparently terminal (finally thrust aside by growth of stems), 

 peduncled ; scales cuneate, closely imbricate, apex often long-acu- 

 minate upcurved, anthers in groups of 3-5. Carpophylls numerous, 

 crowded round apex of the stem, densely woolly, appressed at first 

 into an apparently terminal cone, then spreading (and stem con- 

 tinuing its growth' through them), elongate, flattened, dilated above 

 into an entire, crenate or pectinate blade. Ovules 2-10, in notches 

 on the margins of the lower part of the carpophyll, distant, alternate 

 or opposite, nearly erect. Seeds ellipsoid or globose. 



Cvcadean stems can easily be distinguished from those of the pahns with which 

 they are sometimes confused, but in no way allied, by the petiole-scars being arranged 

 in bands, the bands with large scars being those of the large foUage leaves, the 

 small scars those of the alternating scale leaves. 

 I. Sides of leaflets flat (or margins only recurved in pectiitata) :— 



A. Blade of carpophylls lanceolate, not very deeply pectinate :— 

 Male sporophylls ending in an upcurved spine. Blade of fern. 



lanceolate toothed or shortly pectinate, teeth sometimes 



spinous 1. circinalis. 



Male sporophylls shortly acmuinate. Blade of female a long 



simple acumen without teeth . . . . .2. Rumphii. 



B. Blade of carpophylls orbicular, long-acuminate and deeply 



pectinate. Male sporophylls deltoid and much thickened 



with a long abrupt subulate acumen . . . .3. pectinata. 



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