OF ARTS AND SCIENCES : FEBRUARY 13, 1872. 399 



438. Eriogondm elatum Dougl. in Benth. Eriog. 1. c. ; Gray, 

 Rev. Eriog. 1. c. p. 168. 



439. EriOgonum dichotomum Dougl. 1. c. ; Gray, 1. c. p. 175. 



440. Eriogonum vimineum Dougl. 1. c. : Gray, 1. c. p. 177. 



441. Rumex salicifolius Wirrim. ; Hook. 1. c.^ 



442. Rumex Acetosa L. ; Hook. Fl. Bor.-Am. 2, p. 129 ; spar- 

 ingly collected. 



443. Polygonum nodosum Pers. ; Meisn. in DC. 1. c. 



444. Polygonum amphibium L., var. terrestre Willd. 



445. Polygonum Bistorta L. ; Hook. Fl. Bor.-Am. 1. c. 



446. Polygonum Davisle Brewer, n. sp- (Fl. Calif, ined.) A 

 remarkable species, with a low, branching, commonly zigzag, very 



* Rumex Britannica L. I think I have been able to determine the Rumex 

 to which Linnaeus gave this unfortunate name. The source of the name is to 

 be found by following up his reference to "Mat. Med. 17," i. e. Materia Medica, 

 paragraph 177 (not 17), where, under reference to Fl. Suec. 292, "Europae nos- 

 tra? paludes," is added " Pliarm. Herbce Britannicce radix." The North American 

 plant to which he applied this name was one in his herbarium sent to him by 

 Gronovius from Clayton's herbarium of the Flora Virginica. The fruit of it is 

 not well developed, but the slender pedicels and the foliage show that it is the R. 

 orbiculatus of the later edition of my Manual. But the specimen retained in Clay- 

 ton's herbarium to represent the species, and the only Rumex in that herbarium, 

 is quite different, has some long-awned teeth to the valves, and is, as I believe, 

 R. obtusifolius. The difference in the plants accounts for the remark of Linnaeus : 

 " Plantam Gron. in Fl. Virginica habui a CI. Authore, quae non rubra erat caule 

 aut costis." For Clayton's character, as printed by Gronovius in the first edition 

 of Flora Virginica, was : — " Lapathum foliis longis latis vix acuminatis, costis 

 caulibusque rubentibus, radice intus crocea." That probably relates to the plant 

 retained by Gronovius. And the specimen sent was perhaps Clayton's other spe- 

 cies, viz., — " Lapathum aquaticum foliis longis," &c., which Linnaeus referred to 

 R. vertieillatus. As to the R. Britannica of Michaux, Pursh, and even Meisner, it 

 is uncertain whether they had in view the plant called by me in the Manual by that 

 name, but named by Professor Wood R. altissimus, or that which Wood and prob- 

 ably Pursh took for R. Britannica, and I named R. orbiculatus. The latter proves 

 to be the Linnaean species, and must claim the name, unless that be regarded as a 

 nomenfalsurn, in which case we must take up that of R. Claytoni Campdera, who 

 may be presumed to have meant the Linnaean plant, although there is nothing in 

 his character to certify it. A considerable difficulty in identifying the Linnaean 

 species by the description grew out of the comparison in the species Plantarum 

 with R. vertieillatus, with which when in fruit it has little in common, except the 

 slender pedicels. It should also be noticed that there is a transposition in the 

 naming of the specimens in the Linnaean Herbarium, which, however, has been 

 corrected by Smith. 



