258 Mr. J. Miers on Ephedra. 



decussate, each series consisting of three involucels vaginately 

 united at base ; the flowers, from twenty-five to thirty in each 

 spikelet, are therefore ternately verticillate in each series. The 

 perigonium is petaloid, of the usual form, of dehcate reticulated 

 texture, the areoles being generally disposed in longitudinal 

 rows sometimes anastomosing with each other, each areole being 

 isolated and replete with a coloured fluid ; there is no vestige of 

 any nervure or spicular cells as in Welwitschia. The involucels 

 are similarly reticulated, but they finally become thickened, 

 opake, and coriaceous, except round the margins ; the coriaceous 

 portion is constituted in the manner described in a preceding page 

 (p. 250). The fructiferous spikelets, upon distinct but similar 

 plants, are two to four in each node, 4 to 4i lines long, 2 lines 

 broad, verticillately disposed, each upon a separate pedicel ; 

 their involucels, in about five gradufilly decreasing imbricated 

 pairs, are smooth, opake, subcoriaceous, with almost obsoletely 

 membranaceous margins. The two terminal achenia, half in- 

 vested by the last pair of involucels, are ovate, somewhat attenu- 

 ating upwards, trigonous, with an obtuse pallid perforated sum- 

 mit, the tubillus, with lacerated apex, being scarcely exserted*. 



The variety striata of Gillies possesses all the specific features ; 

 but the branchlets are less than half the thickness, they are 

 glandularly scabrid, of a pallid colour; the internodes in the 

 male plant scarcely exceed an inch, while those of the fructiferous 

 plants are 1 to 1^ inch apart; the leaves, 2^-3 lines long, are 

 united for above half their length into a 3-fid vaginant tube. 

 There are about six smaller glomerated heads around each node. 

 The fructiferous spikelets are 3 lines long, 2 lines broad, with 

 three pairs of subcoriaceous involucels with scarious margins, 

 the terminal pair enclosing two finely striated, opake, fuscous 

 achenia. It may probably form a distinct species ; but there is 

 little that can be characterized. 



7. Ephedra Americana, H. B. K. ii. 2 ; Rich. Conif. 31. tab. 29; 

 Meyer, Mem. Acad. Petrop. v. 100; — ramulis graciliusculis, 

 erectis, subflexuosis, striatellis, pallide virentibus, vix scabrel- 

 lis ; foliis oppositis, imo ad nodos in vaginam brevem nexis, 

 lobis liberis longiusculis, linearibus, subulato-acuminatis, 

 erecto-patulis, submembranaceis, glaberrimis, crebre striatellis, 

 serius ruptis et divaricatis, linea transversali tunc nexis : spi- 

 cellis 6 axillaribus, sessilibus, subglobosis, oppositis vel 4-ver- 

 ticillatis; involucellis per paria 8-10, floriferis, imbricatis, 

 valde concavis ; perigonio paulo longiore, petaloideo ; columna 



* Ample details of structure, and a figure of the plant, will be given in 

 Plate 11 B. 



