24 BULLETIN" 468, U. S. DEPARTMENT OF AGRICULTURE. 



foods in Porto Rico, Hawaii, and the Philippines, ranking in Porto 

 Rico, for instance, next to the sweet potato in importance. 



In appearance tubers of comparable size look much like sweet pota- 

 toes, while in flavor and in composition yams very closely resemble 

 potatoes. (See p. 27.) They have not, however, the keeping 

 qualities of sweet potatoes, and in countries where they grow 

 are usually left in the ground until required for use. Experience 

 and experiment alike show that yams can be readily prepared in 

 acceptable ways and are to be regarded as an important carbohydrate 

 food in regions where they are available. They are prepared for the 

 table in much the same way as potatoes and sweet potatoes. 



Starch is made from the yam and also a flour used in tropical coun- 

 tries as a breadstuff. Like the flours and starches prepared from 

 other edible roots, these yam products are not used alone for making 

 yeast-raised bread, since they do not contain the gluten which is 

 characteristic of wheat flour and which gives the light, porous texture 

 to wheat bread. According to experimental evidence, 96 per cent of 

 the carbohydrates present in yams is assimilated on an average. 



DASHEEN, TARO, AND YAUTIA. 



Dasheen, taro, and yautia are closely related botanically and are 

 so much alike in general character and the uses to which they are 

 put that they may be grouped together for discussion. They belong 

 botanically to the Arum family, which includes also the large-leafed 

 ornamental plant called Caladium or " elephant's ear," frequently 

 seen in gardens, as well as the calla lily and the Indian turnip or 

 j ack-in-the-pulpit. Another member of the Arum family worthy of 

 mention is the tuckahoe or Virgina wake-robin {Pentandra vir- 

 gvnica) , which is closely allied to the tropical America yautia. The 

 tuckahoe grows in marshy bottoms and river banks. Its roots, like 

 those of the yautia and Indian turnip, are very acrid when raw and 

 are full of needles of oxalate of lime, but when cooked are of a very 

 good flavor and much like the other aroid roots. The American 

 Indians are said to have made a kind of bread of the tuckahoe, and, 

 as the earlier records show, tuckahoe was of considerable importance 

 to the pioneer settlers of the United States. 



The dasheen, taro, and yautia all form large underground root- 

 stocks or corms, in which starch is stored, and they are important 

 food plants in many tropical and subtropical countries. Taro is 

 an important crop in Hawaii and, indeed throughout Polynesia, 

 and from it the Hawaiians make the cooked and slightly fer- 

 mented paste called poi, a characteristic and very important article 

 of their diet. Taro, dasheen, and especially perhaps yautia, are 

 common in Porto Rico, and it was largely through the experiment 



