277 



Trinidadian No. 2 gave the largest yield, viz., ii tons 7| cwt 

 This variety gives very large cordate tubers of good quality — 

 "Trinidadian No. i" and "Fire Brass" come second with a yield 

 of II tons, 



I am inclined to place Trinidadian No. I in the highest position 

 and to class it as the best variety in this series on account of the 

 high quality of the tubers both in total solids and in starch and 

 sugars. Our results with this new Trinidad seedling are such as 

 to warrant its general trial by the people all over the island. 



Chemical Analyses. 



Samples of all the varieties were sent to the Laboratory and 

 records taken of the average weight of a tuber, its general appear- 

 ance and of the flavour when cooked. The latter was decided 

 upon by a small committee consisting of a chemist and three ex- 

 perienced black ladies. On the whole their verdict is in substan- 

 tial agreement with the opinions of Mr. Cunningham which were 

 arrived at quite independently and based upon different samples 

 of the tubers. 



The variety with the highest percentage of total solids is 

 " Governor" with the very high content of 39.8 per cent. Trinidadian 

 No. 2 gave the lowest result with 30.58. Even this is far above 

 the average American sweet potato which contains only 29 per 

 cent, of total solids. 



The variety " White Sealy," heads the list in starch content with 

 30*94, a truly extraordinary amount. The lowest starch content 

 is that of " Fire brass" with 2374 per cent. 



The sugars vary from 2*94 per cent, in " Thompson's favourite" 

 to only 0*232 per cent, in "Fire brass," 



The fibre shows little variation ("567 to *828). 



The nitrogen content varies from 0*7 in Thompson's favourite 

 ( = 4*7 per cent of protein) to 0*16 in Trinidadian No. 2 ( = i per 

 cent, protein). 



A determination of amides in the variety " Tailor's scissors" in- 

 dicated that rather over one-fifth (22*2 per cent) of the total nitro- 

 gen exists as amides. 



The results shown by the analyses of this series of varieties 

 indicate that the sweet potato as grown in Jamaica is a food of 

 very high (|uality. The bulk of the solid matter consists of starch. 

 The standard of solids and of starch shown by this collection of 

 varieties is far in excess of that obtaining with sweet potatoes 

 grown in the United States and places the tropical product in a 

 very favourable position by comparison. With regard to the 

 ' sweetness' of the sweet potato, the indicated proi5ortion of sugars 

 is p.ot enough to account for the sweet taste of the tubers when 

 cooked and eaten. 



To test whether the process of cooking increased the sugar 

 content, an experiment with the variety Trinidadian No. I was 

 carried out. 



