ex. PALMiE 



643 



forming a Hard, horny substance, wMch, wlien tlie seeds germinate, is 

 converted into sugar. 



The base of petioles as a rule occupies tlae entire circumference of the trunk, and 

 consequently the leaf -traces (fibro-vascular bundles) of each leaf enter the stem from 

 all sides. If we follow their course downwards we find that in their upper portion 

 they bend towards the centre of the stem, while lower down they gradually bend out- 

 wards, and (frequently uniting with the traces of earlier leaves) run down near the 

 circumference of the trunk. In their upper portion each leaf-trace consists of a few 

 vessels which in Calamus and other scandent palms (as in Vitis and other climbers) 

 are very large, over 0*5 mm. diam., with thin-walled phloem, tracheides, and paren- 

 chyma, as well as a large mass of thick-walled wood-fibres, whereas the lower portion 

 almost entirely consists of thick-walled wood-fibres. The space between the fibro- 

 vascular bundles is occupied by parenchymatous tissue, which as a rule predominates 

 in the centre of the trunk. Hence it follows that the hardest portion is near the 

 outside of the trunk, consisting mainly of closely packed bundles of wood-fibres. 

 Near the centre the tissue is softer, and hence in some species old stems are often 

 hollow. 



Preparatory to the production of flowers and seed the parenchyma in the trunk of 

 Phcenix and other genera (analogous to what we find in the Beech before a seed! 

 year) is full of starch, which at the time of flowering is transformed into sugar. The 

 starch of many species is utilized as Sago, while the sugary sap is obtained either 

 from the cut spadix or (in the case of Phcenix) from the trunk below the crown of 

 leaves. 



I. Leaves pinnate or pinnatisect. 



A. L. simply pinnate, leaflets induplicate, no 



midrib, fl. dioecious . , . . .1. Phcenix. 



B. L. simply pinnate, leaflets, in the species here 



described, linear or lanceolate with midrib 

 and reduplicate sides, the terminal leaflets 

 often confluent as a plaited limb. 



(a) Spadix androgynous, on the stem 

 below the leaves. 



a. Tips of spikes with 6 only. 



$ fl. minute, stamens 3 or 6, 



anthers basifixed . 

 S fl. in the axils of broad bracts, 



stamens 6, anthers versatile , 



2. Aeeca. 



Ptyghoe APHIS (p. 647). 



j3. S fl. in upper portion of spikes, 

 both sexes in lower portion, fl. 

 sunk in cavities of the spike 



y. Clusters of 3 fl. (1 ? between 2d) 

 all along the spike, stamens 

 numerous . , . . . 



3. Bbntinckia, 



4. PiNANGA. 



(b) Spadix among the leaves. 



a. Erect, unarmed, spadix usually 

 unisexual, fr. sessile, epicarp 

 smooth, naked. 



(1) Stems tall, stout. 



Leaflets praemorse, auricled, 

 stamens oo . . . . 

 Leaflets acute, stamens 6 



(2) Tufts of large 1. from a creep- 



ingrWzoL. . . . 



§, Mostly climbing, armed, epicarp 

 clothed with scales, usually 

 shining. 



(1) Stem short or none . 



(2) Stem elongate. 



Spikelets concealed under large 

 spathels . . . . 



Spikelets in the axils of large 

 cymbiform or open de- 

 ciduous spathels . 



5. Aeenga. 



6. Cocos. 



NiPA (p. 648). 



7. JZalacca. 



8. Plectocomia. 



9. BiEMONOJiOPS. 



