ROSACEAE. — PRUNUS 251 



integra, glabra; petala orbicularia, 15 mm. longa, emarginata; stamina 41, 

 petalis dimidio breviora; stylus glaber. 



Nippon: Swasima, April 2, 1879, /. Matsumura (kindly sent to me by Professor 

 Matsumura, under the name of P. pseudocerasus, /3 spontanea). 



The species can be distinguished from P. pseudocerasus Lindley by the glabrous 

 under side of the leaves, and from P. serrulata Lindley and P. Sargentii Rehder 

 by the pubescent upper side of the leaves. As I do not know to which of these two 

 species it could be referred as a variety, I consider it necessary to give it provisorily 

 a specific name. From P. parvifolia Koehne it is distinguished by the quite different 

 shape of the leaves. 



51. Prunus parvifolia (Matsumura) Koehne, n. sp. 



Prunus pseudocerasus, var. parvifolia Matsumura in Tokyo Bot. Mag. XV. 101 



(1901). 

 Prunus pseudocerasus, var. iypica, subvar. parvifolia Koidzumi in Tokyo Bot. 



Mag. XXIII. 182 (1909). 

 P. jamarakura, a elegans, a parvifolia Koidzumi in Tokyo Bot. Mag. XXV. 

 186 (1911). 



Ramuli novelU glabri. Petioli 6-10(-13) mm. longi, dense villosi; glandulae 

 plerumque 2 crassae petioli apici v. laminae basi insertae; lamina ovata v. rotun- 

 dato-obovata v. obovata v. obovato-oblonga, 3-7.5 cm. longa, 1.5-4 cm. lata, 

 acuminata, setaceo-serrata, supra pilis persistentibus conspersa, subtus glabra 

 V. initio tantum tenere pilosa mox glabrata, nervorum paribus 7-10. Involucra 

 pleraque sub anthesi decidua, paucissima persistentia circ. 1 cm. longa; pedunculus 

 4-10 mm. longus, glaber v. superne parce pilosus; florcs (l-)2-3 umbellati v. 

 subumbellati, coaetanei foliis sirnul 3-4 cm. longis; bracteae 4-7 mm. longae, 

 herbaceae; pedicelli 13-26 mm. longi, glabri v. hinc inde parcissime pilosi; cupula 

 5.5 mm. longae, obconico-tubulosa, glabra; sepala 4 mm. longa, integra, ciliata; 

 petala rotundata, 13 mm. longa 11m. lata, bilobo-emarginata; stamina 32, petalis 

 fere dimidio breviora; stylus glaber. Drupa globosa, 7 mm. diam.; putamen 

 rotundatum, 6:6:4 mm., obsolete sulcatum. 



Japan: Sterile twig, F. von Siebold (in the Rijks-Herbarium, Leyden, as Cerasus 

 donarium Siebold, mixed with a flowering twig of Prunus pseudocerasus virescens). 

 Cultivated in the Botanic Garden of the Agricultural College of the Imperial 

 University of Tokyo, April 1908, Koidzumi (kindly sent to me by Matsimiura as 

 P. pseudocerasus parvifolia Matsumura and as P. pseudocerasus typica parvifolia 

 Matsumura); from the same garden, a sterile twig, without date or collector; a 

 sterile twig, June 22, 1901, Komaha. 



Matsumura gives as the Japanese name Jugatsu-sakura, i. e. October-Cherry; 

 he also states that the plant flowers in October. It is therefore strange that 

 the flowering branches communicated to me are dated April. The species is very 

 different from P. pseudocerasus Lindley. It might possibly be placed with P. 

 serrulata Lindley or with P. Sargentii Rehder, but it differs so much from both 

 that I must consider it a distinct species. 



Prunus parvifolia, forma aomoriensis Koehne, n. forma. 



Lamina foliorum sub anthesi jam 3.5-5.5 cm. longa, subtus versus costae basin 

 densiuscule pubescens ceterum glabra. Involucra sub anthesi fere omnia persis- 

 tentia, ad 15 mm. longa; pedicelli densiuscule pilosi v. superne glabri; cupula 

 5.5-6 mm. longa; sepala margine glabra; petala 15 mm. longa, 10 mm. lata. 



Northern Nippon: Aomori, May 1898, U. Faurie (No. 2093). 



52. Pnmus concinna Koehne. See p. 210. 



53. Pnmus Twymaniana Koehne. See p. 211. 



