1963] 



TAXONOMY OF LUZULA SUBGENUS PTERODES 



301 



7a. Luzula rostrata Buehenau var. rostrata 



Luzula rostrata Buehenau, Das Pflanzenreieh 25(4) : 47. 1906. 



This variety is distributed in the higher mountainous regions of Japan (Fig. 

 8). It can easily be distinguished from variety jimboi by the smaller flowers that 

 are dark purple, and by the smaller ovate anthers and the straight caruncle. 



Type. Fa uric 2700, collected in Matsumura, Japan, (not seen.) 



Kepresentative Specimens: JAPAN: Honshu: A. Eitazaua (June 20, 1958) (TXS): If. 

 Matsuda (July 26, 1957) (TXS) ; 8. OJeuyama (July 20, 1936) (TXS) ; K. Shiota 3379 (GH) ; 

 S. Sugaye (Aug. 19, 1952) (TXS). 



Hybrids. No naturally occurring hybrids have been reported and none were 

 found during this study. Although this variety occurs in Japan the possibility 

 that it hybridizes with Luzula plumosa var. brevipes from this region seems re- 

 mote. This results from two peculiarities of this species ; first, it blooms much 

 later in the year than does L. plumosa var. brevipes, and second, it is restricted 

 to the mountainous regions of Japan while var. brevipes is usually found at lower 

 altitudes. 



7b. Luzula rostrata Buehenau var. jimboi | Miyabe & Kudo) Ebinger, comb, 

 nov. 



Luzula jimboi Miyabe & Kudo, Trans. Sapp. Nat. Hist. Soc. 5: 37. 1913. 

 Luzula elata Satake, Jour. Jap. Bot. 14: 260. 1938. 



This variety is generally restricted to northern Japan, the Kuril Islands, and 

 the Kamchatka Peninsula (Fig. 8). It is easily distinguished from the more 

 southern variety by the larger flowers that are not purple, the anthers that usu- 

 ally equal or exceed the filaments in length, and the curved caruncle that is 

 usually as long as the seed. 



Type. K. .limbo. June 13, 1891, collected on the Kurile Islands, Etorofu. (Not 

 seen.) 



Representative Specimens: JAPAX: Honshu: K. Kimura (Julv 30, 1928) (TI), (July 

 15, 1929) (TI); Y. Momiyama (July 4, 1931) (TI) ; S. OJeuyama "(July 21, 1934) (TXS); 

 Y. YamazaM (Aug. 5, 1954) (TI). Hokkaido: 8. OJeuyama (July 18, 1941) (TXS); Satake 

 (July 28, 1931) (TI) ; K. Una 2596 (GH) ; /. Yamamoto 4322 (TI). KURIL ISLAXDS: S. 

 Bergman 122 (S), 176 (S), 362 (S). RUSSIA: (Kamchatka Pen.): W. Eyerdam (June 27, 

 1928) (S), (July 10, 1928) (S) ; E. Hulten 191 (GH), 2183 (S), 3816 (S) ; V. L. Eomarov 

 (June 18, 1908) (S), (June 22, 1908) (K), (June 23, 1909) (K). 



Hybrids. No naturally occurring hybrids have been reported and none were 

 found during this study. 



This species is easily distinguished from the other Asiatic ones by the cauline 

 leaves that taper abruptly to a callose-tip. The erect pedicels of the inflorescence 

 and the large curved caruncle also serve to separate it from Luzula plumosa var. 

 brevipes and L. rufescens. Although this species does come into contact with L. 

 plumosa in Japan it is unlikely that they hibridize. This lack of hybridization is 

 probably a result of differences in blooming period and habitat. L. plumosa var. 

 brevipes blooms in April and May and generally grows at low altitudes. In con- 

 trast, L. rostrata flowers in late June, July and August and the specimens from 

 Japan appear to grow at much higher elevations. These two conditions indicate 

 that hybridization between these two species, rarely, if ever takes place in nature. 



