1919] REIIDER, NEW SPECIES, VARIETIES AND COMBINATIONS 137 



ULMACEAE 



Ulmus glabra f. comuta, comb. nov. — U. campcstris cornuta David in 

 Rev. Ilort. ser. 2, iv. 102 (1845 46).— U. triserrata Hort. apud Kirchner 

 in Petzold & Kirchner, Arb. Muse. 507 (1804).— U. intermedia Hort. ex 

 Kirchner, 1. c., as synon. — U. scahra e. U. tricuspis K. Koch, Dendr. ii, 

 pt. I. 415 (1872). — U. tridens Hort. ex Koch, 1. c, as synon. — U. mon- 

 tana var. triserrata Lavallee, Arb. Segrez. 237 (1877).— U. montana var. 

 tridens Lange, Haandb. Dansk. FI. 267 (1887).— U. scahra f. tricuspis 

 Dippel, Handb. ii. 29 (1892). — U. montana f. lobata Waisbecker in Oestr. 

 Bot. Zeitschr. xlix. 07 (1899). — U. montana ? tricuspis Sclielle in Beiss- 

 ner, Sclielle & Zabcl, Handb. 86 (1903). — U. scahra f. hcterophyJla 

 Schneider, Ilandb. Laubh. i. 218 (1904), pro parte.- U. montana a. corij- 



lifol 



U. glabra f. tricuspis 



Rehder in Mitt. Deutsch. Dcndr. Ges. xxiv. (1915) 216 (191G). 



This form has large leaves which are partly, at least at the ends of the 

 more vigorous branches, 3- or sometimes 5-lo1)ed at the broad apex. It 

 has usually been confused with U. laciniata Mayr ( U, major var. hcterO' 

 phylla Maxim. & Rupr.), a species of Eastern Asia, chiefly distinguished by 

 its light colored brancldets and by the leaves which are nearly all 3-lobcd 

 at the apex, such leaves not being confined to the end of the more vigor- 

 ous branches, as in this form of U, glabra. 



Ubnus laciniata IVIayr var. nikkoensis, var. nov. 



A typo praccipue recedit foliis minoribus latioribus subtus sparse pubes- 

 centibus junioribus i)lus minusve purpurascentibus. — Folia late oIx)vata 

 apice plerumque triloba, 6-11 cm. longa, subtus scabrida pilis brevibus 

 satis sparsis in costa et nervis venulisque, ceterum glabra; raniuli annotini 



fusco-clnerei. 



Japan. Hondo; Nikko region, Lake Chuzenji, alt. 1000 m., plants col- 

 lected by J. G. Jack, October, 1905, and growing now in the Arnold Ar- 

 boretum. 



This variety differs chiefly in its smaller, usually broadly obovate leaves 

 rather sparingly short-pubescent on the nerves and veinlets 1>eneath and 

 scabrid to the touch, while in the typical form the under side of the leaves 

 is covered by a grayish rather dense and soft pubescence and the leaves are 

 oftencr oblong-obovate and usually more than 10 cm., often to 15 cm. long. 

 According to our growing plants the variety forms a smaller tree of slenderer 

 habit particularly striking in spring on account of the pur]>lish color of the 

 unfolding leaves which is retained a long time and changed in summer to 

 dark green, while the leaves of the typical form are light green when 



unfolding. 



I have seen no herbarium material of U. laciniata from Hondo, but ac- 

 cording to Japanese botanists it occurs in central Japan. Tlie specimens 

 from Hokkaido I have seen belong to the typical form and agree with 

 specimens from Manchuria. 



