107 



Diagnoses of some Ne^w Plants from South 

 Australia, 



By Baeox Sir P. to]!^ Mueller, M.D., T.E.S. &c. and 

 Professor Ealph Tate, F.Gr.S., F.L.S. &c. 



[Read August 7, 1883.] 



Dimorphocoma. 



Flower-head nearly bell-shaped. Bracts forming the in- 

 volucre nine or ten, herbaceous, in two rows, narrow-lanceolate, 

 lieceptacle without special bracts. Flowers few. Corolla of 

 the outer flowers radiating with short and narrow ligules ; 

 stamens none ; style enclosed ; stigmas exceedingly thin, 

 rather acute. Innermost flowers bisexual, very few in 

 number ; corolla tubular, with five short tooth-like lobes ; 

 anthers very short, rounded at the base ; stigmas very thin, 

 papillular. Achenes of the anantherous flowers fertile, 

 obconic-oblong, densely silky ; their pappus consisting of 

 numerous capillary bristles in several rows unequal in length, 

 and of five or six linear-lanceolate inner scales. Achenes of 

 the bisexual flowers exceedingly slender, glabrous ; their pappus 

 formed by a few very short bristles. 



A minute annual of Central Australia, having much the 

 aspect of Vittadinia australis, with short hairs, with oblong- or 

 narrow-lanceolar leaves at the base and along the stem, with 

 terminal solitary small flower-heads almost sessile or on short 

 peduncles, and with whitish rays of the outer flowers. 



The genus, thus defined, differs chiefly from Elachanthus and 

 Isoetopsis in its anantherous flowers being ligulate, and in 

 having the pappus of the fertile fruits provided not only with 

 scales, but also with bristles ; from Isoetopsis it is furthermore 

 distinct in habit ; from Minuria it is separated by its fewer 

 and broader involucral bracts, and by its anantherous flowers 

 producing a scaly as well as bristly pappus. 

 Dimorphocoma minutula. 



On barren stony ground, forming the western slope of 

 Mount Parry, in the Aroona-Eange, towards Lake Torrens. 

 B. Tate. 



The specimens vary from one and a-half inch to four inches 

 high, beset with septate hairs. Stems one or two or few, erect 

 or ascending. Eoot very thin, attaining a length of three and 



