FLORA OF SOUTH AMIiUIC.V AND THE PACIFIC 19 



the middle of the venules (lateral). Besides the affinity that 

 MesocldcBna has with the above mentioned genera, it also, in ap- 

 pearance, exliibits some siniilarity in habit and form of tlie sori 

 to those species of Diplazium which have regular bipinnatifid 

 fronds and short sori ; but the latter genus is readily distin- 

 guished by having a laterally attached indusium on each side 

 of the venules, whereas in Mesochlctna^ the venules produce 

 only a simple sorus, with the indusium attached along the 

 centre of the venule, and like the generality of Aspidieof is 

 very fugacious." 



J. Smith. 



III. — Contributions towards a Flora of South America and the 

 islands of the Pacific. By Siu W. J. Hooker, LL.D., 

 and G. A. W. Arnott, Esq., LL.D. 



L EXTRA-TROPICAL SoUTH A.MLRICA. 



(Continued from page 254 of Vol. II. of tie Companion to the Botanical 



Magazine.^ 



Subtribe IL BAccHARiDEiE. Less. 



Plagiocheilus. //. et A. De Cand. Prodr. \'\. p. 142. 



Involucrum subtriseriale foliolis obovato-oblongis. Pachis 

 hemisphasrica. Flares fteminei multiseriales in anibitu, reii- 

 quis paucis masculis. Achenium calvum, oblongo-obovatum, 

 compressum, puberulum, erostre. Ovarium fi. masc. nullum. 

 Corolla fcem. tubo brevissimo, limbo obliquo subbilabiato, 

 labio exteriore horizontaliter patulo, tubum subsequante, 

 interiore brevissimo utroque integerriino ; masc. tubo brevi- 



usculo gracili, limbo campanulato Ilerba ramosa, erecta, 



pilosula. Folia alterna, interrupte pinnatijida, laciniis iiiciso- 

 pinnati/idis, hasi auricrdata, auriculis incisis, amplectantibus. 

 Capitula subglobosa, corymboso-pamculata, lutea, vix Grauget-e 

 7nagnitudine. 



1039. (I.). P. tanacetoides, H. et A.—De Cand. Prodr. v. 



\'].p. 142 Coastof the Parana, in sandy places. Tweedie. — 



The female florets are very remarkable, resembling the mouth 

 of an ewer. What we here speak of as an inner lip to the 



