42 DIOjsCOEEACE^. 



Dioscorea pseudojaponica Hayata sp. nov. (Fig. 21). Volubilis ; caulis 

 complanato-teres glaber. Folia opposita triangulari-ovata vel -oblonga cliartaceo- 

 membranacea 6-10 cm. longa 5}-6 cm. lata apice caudato-acuta basi lata auri- 

 culata niargine subintegra 7-nervia utraque glabra, petiolis 3-4 cm. longis glabris 

 gracilibus. Fl. J : spicati, spicis ad axillas foliorum verticillatim sitis simplici- 

 bus 3 cm. longis glabris gracilibus triquetris subalatis, floribus sessilibus semi- 

 clausis, bracteis tiiaugularibus cuspidatis 1 mm. longis ; periantliium globosum 

 2 mm. in diametro, segmentis 6 rubro-punctatis valde imbricatis, 3-exteriori- 

 bus majoribus rotundato-oblongis l^ mm. longis valde concavis glabris apice 

 obtusis, interioribus minoribus ; staminibus 6 subsessilibus, antlieris oblongis 

 I mm. longis apice emarginatis ; rudimentum ovarii 0. Flores ? : ignoti. 

 CapsulsB cum alis late reniformes 3 cm. latae 18 mm. longse basi apiceque 

 cordatse. Semina valde complanata circumcirca ala membranacea cincta cum 

 alis 18 mm. in diametro. 



Dioscorea japonica et rldpogoiioides Hayata Gen. Ind. p. 84. 



Hab. SMcliiseitonzan, Rarazan, Gukutsu, Ritozan, Maso, Kelung, Tam- 

 sui, Gaogan, Taikokan, Bydritsu-Taiko. 



Very near Dioscoi^ea japmiica Thunb. ; but dififers from it in the much 

 larger capsules and in the quite obtuse anthers which are not appendiculate 

 at the apex. 



Dioscorea alata Linn. (Fig. 22). Volubihs ; cauhs teres glaber Igevis 4- 

 alatus, ahs undulatis 1-2 mm. latis. FoHa opposita oblongo-cordata vel oblongo- 

 criangularia 10-12 cm. longa 5-Q cm. lata apice acuminata basi cordata vel 

 tordato-auriculata ad centrum acuta margine integra chartacea utraque pagine 

 glabra 7-nervia, nervis supra haud subtus prominente elevatis, venulis 

 tenuissimis, petiolis 5-6 cm. longis gracihbus glabris tenuiter 4-alatis, 

 alis basi decurrentibus ad auriculas dilatis. Kacemi axiUares fructiferi 

 15 cm.-20 cm. longi glabri 4-alati. Capsulae prematurse cum aKs in ambitu 

 obovoideae, ahs 3 latis 5 mm. latis basi attenuatis, stipitibus 2 mm. longis 

 glabris. 



Hab. Banchoryo: Rono, leg. U. MoRi, No. 5523, Nov. 1907. 



Nearly identical with the figure given in Wight Ic. t. 810 ; but somewhat 

 diflfers from it in having ovately cordate leaves. 



I 



