AGRICULTURAL INDUSTRIES. 67 



perceive a rapid diminution in its cultivation, and one that is caused 

 much less by difference of climate than by a change of taste and 

 the prevalence of substitutes, such as chestnuts and sweet-potatoes. 

 Thus, in Northern Italy it occupies 0'33 per cent, of the area; in 

 Central Italy, 0*24 per cent, but in Southern Italy, only o-03 per cent. 

 A similar diminution is seen on the Iberian Peninsula. This, too, 

 explains why the potato was not long ago carried to Japan by the 

 Portuguese. They found it desirable to introduce tobacco, grape- 

 vines, and quinces (from which a favourite sweetmeat is made in 

 Spain and Portugal), but not Solanum tuberosum. 



Aracece, so much cultivated on account of their bulbs, do not 

 bloom in the fields any more in Japan than elsewhere, since they 

 can only go through one period of vegetation there, and that does 

 not suffice for them to put forth stalks. So they remain in the low 

 herbal or monopodal form. This renders it rather hard to dis- 

 tinguish them. The most prized and most widespread kind not 

 merely in Japan, indeed, but throughout the whole monsoon- 

 region and Polynesia, is : — 



8. Colocasia mitiquomm, Schott [Arum esciilciitum, L.), which 

 the Japanese call usually simply Imo, or Sato-imo (village-potato). 

 But the South-Sea Islander calls it Taro. Other Japanese 

 names distinguish different sub-species. At the ends of short 

 sprouts (stoles), the axillary buds develop in several directions 

 from the mother-bulb (Oya-imo), which resembles a rhizome. 

 These buds become fleshy white tubers (Ko-imo), in the shape of 

 an ellipsoid or ovate, about the size of a hen's ^%g and weighing 

 from 60 to 80 grs. Of carbon-hydrates, they show more glucose 

 and dextrine than starch, — hence their peculiar sweetish flavour. 

 Propagation takes place by means of bulbs, as in our potatoes. 

 The petioles of the Sato-imo are green and longer than in most 

 other kinds of the imo belonging to this division ; the shield or heart- 

 shaped leaves themselves larger. On the upper side they are a 

 polished green, on the under side, a greyish white. 



9. Leucocasia gigantea, Schott {Caladium esculentum, Sieb.), Jap. 

 Hasu-imo, resembles the foregoing closely, but is nevertheless not 

 so much prized and planted. 



10. Alocasia macrorrJiiza, Schott {Arum macrorrJiisum^ L. ; 

 Colocasia esculentum^ var. C. and Z.), Jap. Manshiu-imo. This 

 kind, likewise widely grown in the South Sea under the name of 

 Taro, and elsewhere too, forms only one large bulbous rhizome. 



11. Couophallus konjak, Schott {Arum Dracunculus, Th.), Jap. 

 Konniyaku (pronounced Konjak), produces a single bulb, like the 

 foregoing kind, only much smaller. It serves in the preparation 

 of a gelatinous, tough food, which bears the name Konniyaku. 



Of yams, or dioscorece, the Japanese use the following : — 



12. Dioscorea japonica, Thunb. {D. oppositifolia, Thunb.), Jap. 

 Yama-imo, that is, wild potato, or Jinen-j6. It is wide-spread in hill 

 and mountain-forests, up to a height of about 600 m. It twines 



