1851.] Linnean Society. 155 



goneee, from all the known genera of which it is distinguished by its 

 very slender ramifications, which are in every axil dichotomously 

 divided, the solitary involucre on a lengthened capillary pedicel 

 springing from the middle of each bifurcation, and by the proportion 

 of its floral parts. The author gives his reasons for regarding the 

 floral envelopes in Polygoneee as constituting a calyx and corolla, 

 which, in all described Eriogonece, have a ternary arrangement with 

 9 stamina and 3 styles ; but the present genus diflfers in the quater- 

 nary disposition of the envelopes, accompanied by 8 stamina and 

 4 styles. He had at first regarded it as entirely undescribed, the 

 characters of Oxytheca, as given by Mr, Nuttall in the ' Journal of 

 the Academy of Natural Sciences of Philadelphia,' 2nd series, vol, i. 

 p. 169, deviating widely from those observed by himself on the Chi- 

 lean plant ; but the examination of a specimen of Oxytheca from Mr. 

 Nuttall himself, in Sir W. J, Hooker's Herbarium, has convinced 

 him that, notwithstanding these apparent discrepancies, his plant is 

 referable to the same genus, the characters of which he is compelled 

 to modify as follows : — 



Oxytheca, Nutt, 



Char, Gen. Involucrum 3-5-florum, tubulosum, subtetragonum, ad me- 

 dium 4-5-partitum ; laciniis subaequalibus, acutis, longissime aristatis. 

 Flores hermaphroditi cum masculis interdum intermixti, pedicellati, 

 bracteati, subexserti, demum cernui. Sepala 3-4, petaloidea, aequalia, 

 oblonga, unguiculata, valde imbricata. Peiala 3-4, sepalis alterna et 

 subsiinilia, tenuiora, glabra, imbricata, et cum illis persistentia, Ula- 

 mina 6-8, e summo gynophoro orta, inclusa, 3-4 alterna breviora 

 sepalis opposita ; filamenta filiformia, apice inflexa ; antlierm rotun- 

 datee, cordatse, dorsifixse. Ovarium ovatum, 3-4-gonum, stipitatum, 

 petalis tertio brevius, ]-loculare,: ovulo basilari, erecto, Styli 3-4, 

 breves, erecti, demum divaricati ; stigmata capitata. Achcenium 1-sper- 

 mum, ovale, 3-4-costatum, sepalis petalisque emarcidis arete tectum. 

 Semen loculum implens ; testa membranacea. Embryo spiralis, anti- 

 ti'opus, intra albumen farinaceum inclusus ; cotyledonibus cochleato- 

 rotundis, foliaceis, accumbentibus ; radiculd illis triplo longiore, tereti- 

 subulata, hemicyclica, apice recto verticem spectante. — Herbse suffru- 

 ticuloscB Cali/ornicce et Chilenses, Andicolce, sesquipalmares, valde ra- 

 mosce ; ramis gracilihus, in qudque axilla 2-3-chotome divisis ; foliis 

 radicalibus congestis, lineari-subulatis, caulinis bracteiformibus, axilla- 

 ribus, ternis, basi connatis, hinc breviter vaginantibus ; involucre lo7ige 

 pedunculato e qudque dichotomid orto ; floribus minutis, slgiUatim pr<B- 

 cocioribus ; pedicellis basi bractea lineari, aristatd, breviore donatis. 

 Oxytheca spiculata, dicbotome ramosa, ramulis gracilibus divaricatis 

 glanduloso-pilosis, foliis radicalibus congestis spathulato-linearibus 

 utrinque pilis eglandulosis asperis, pedunculo axillari capillaceo, invo- 



