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The Botanical names liere given are those to which it is believed 

 the various species should be referred, but are still given with some 

 diffidence, and only as material for better identification. 



1. Dioscorea alata, L.—liJegvo yam, Barbados yam, white yam. 



2. D — saliva, L. — Yellow yam. 



3. D—Jutea, Mey— Afou yam. 



4. D-glahra, Roxh. ) Chinese yam. 

 D — batatas, Decas J •' 



5. D—trifida, Z-.— Cush-Cush or Indian yam, 



6. D—bulbifera, i^.— Cut and throw away. 



7. D — triphylla, L. 



8. D — polygonoides, H.B.K. 



9. D — Kegeliana, Grisb. 



Dioscorea alata, L. — white yam. 



Stem 4 — Winged, angular ; leaves, opposite, cordate oblong, or 

 cordate ovate with a spreading basilar sinus, glabrous, devoid of 

 pelucid lines. Tuber large, white. 



Under this species we have the following varieties : — 



1. Negro yam of Jamaica. 



2. Barbados Avhite yam, Barbados water yam. 



3. Horn yam. 



4. Snake yam. 



5. Devil yam. 



Of these, so far as the writer's observation goes, the so-called 

 " Negro yam" of Jamaica (var. No. 1) is by far the best for table use. 

 It is very productive and does not take too much room ; the tuber is 

 cylindrical, averaging fifteen inches in length and five or six in 

 diameter. 



No. 2. The Barbados white and water yams also belong to this 

 species, although there is a distinct diiference in the form of the root, 

 which in this variety is palmate or branched like the fingers. Our 

 roots of this variety grown from Trinidad tubers were this year not 

 more than one quarter the size of those grown from sets obtained from 

 the Botanic Gardens, Guiana, eight holes of which produced 327 lbs- 

 gross weight of yam or over 40 lbs. per plant. This variety has also 

 come to us under the name of " Lisbon yam," and it is mentioned in 

 Sloane's Natural History of Jamaica that it obtained this name 

 through being sent via Lisbon to Africa as stores for slave ships. 



" They send them with earth nuts, for Lisbon from St. Thome to 

 victual their slaves by the Avay." — Clusius. 



The 3rd variety, or horn yam, is one which grows into the shape 

 of a curled cow's horn. It has a fine skin, is dry and mealy when 

 well cooked, and is altogether a fine table yam. 



