﻿ON THE BOTANY OF JAPAN. 381 



ered near Hakodadi, and also on the northern end of Nippon, — out of blossom, indeed, 

 but with the ovaries just bursting, and the later specimens with the peculiar seed well 

 formed. The latter, J. Small found at Cape Soya, the northeastern extremity of Japan, 

 in fruit only. So that flowers are Avanted to confirm the identity, of which, however, 

 I have scarce a doubt. CaulophyUum inhabits rich woods, from Canada to the moun- 

 tains of Carolina and northwest to Minnesota ; Diphylleia was known only in the 

 Alleghany Mountains between Virginia and Georgia. 



Supposing these two plants to be satisfactorily identified as to species, are we to 

 regard them as the descendants of a common stock, though now separated by one hun- 

 dred and forty degrees of longitude ■? Or are we to suppose them independently origi- 

 nated in two such widely distant regions % The collocation of a larger body of such 

 facts may lead to a satisfactory answer to these questions. 



Nymphaacece. Zuccarini mentions two undetermined species of Nymphcca. It would 

 no longer be surprising if our iV. odorata should be one of them. INIr. Wright found 

 only Niiphar Japonica, which, in appearance, is intermediate between N. Jutea, of the 

 northern part of the temperate zone generally, and the very local N. sagittafolia of 

 the Southeastern United States. 



Of true Pajjaveracece none seem to be indigenous to Japan, except Chelidonium. 



But Fitmariacece are rather numerous. Mr. Wright gathered three of the seven 

 species of Cori/dalis enumerated by Zuccarini, and the Dicentra spectahilis, now so well 

 known in our gardens. Dicentra 2msilla, Sieb. & Zucc, is likely to be the D. lachena- 

 liceflora, which was collected in the adjacent Okotsk region. 



Besides Arahis hirsuta and A. lyrata, Mr. Wright abundantly gathered the plant 

 which in Perry's Japan Expedition I called A. alpina% var. Japonica, but now con- 

 sider distinct.* The few other Cruciferce, all Old-World species, had been already 

 recorded as from Japan. 



Having barely touched upon the southern island, Kiu-siu, Mr. Wright did not meet 

 with the interesting Flacourtiaceous plant Xylosma [Hisingera) Japonicum, the con- 

 geners of which are mostly in the South Sea Islands and in Central America, &c.f 



* Arabis Japonica (sp. nov.) : pubescens ; caule valido folioso (spithamajo ad pedalem) ; foliis dentatis. 

 radicalibus obovatis oblongisve in petiolum attenuatis, caulinis ovatis oblongisve subcordato-aniplexicaulibus ; 

 racenio densifloro ; siliquis etiam confertis erectis strictis, valvis subplanis nervosis ; stylo brevissimo ; semini- 

 bus anguste alatis (vel apteris ?). Hakodadi and Simoda. 



t M. Clos, in his recent monograph of the Flacoiirtiaceee (Ann. Sci. Nat. ser. 4, 8. p. 220, 227, &c.), recog- 

 nizes the general identity of Hisingera with Xylosma, but keeps up the latter genus on account of the more 

 united styles and stigmas, — a difference only of degree and with no marked limitation. He takes no notice 

 VOL. VI. NEW SERIES. 59 



