AND GENERA OF PLANTS. 339 



very few similar, empty scales. Scales membranaceous, diaphanous, shining, yellowish-white, 

 with a greenish oblong centre, internally with a cleft fold, usually enclosing the greater part of the 

 floret, and always the seed, on the back, at and towards the base, densely tomentose. The recep- 

 tacle, from which the fructiferous scales readily become detached, appears to be a narrow punctate 

 cylinder, or rachis, like that of a spike, round Avhich the scales are imbricated. Stigmas bifid, fili- 

 form, very slender. Of the floret it is diflScult to detect more than a mere hyaline rudiment. Seed 

 (rather than achenium) dark broAvn, minute, cylindric-oblong, somewhat compressed, obtuse, 

 smooth and shining, very acute at base, with only a single thin integument and its lining, as in a 

 naked seed. Somewhat allied to Evax and Micropus, but at the same time very distinct. 



MICROPUS. (Linn.) 



Capitulum few-flowered, heterogamous, flowers all tubular; rays about five, 

 feminine, filiform; discal florets three to five, masculine, five-toothed. Invo- 

 lucrum about five-leaved, conspicuous or minute. Receptacle small, brac- 

 teolate, except the centre, the bractes at length cartilaginous, folded inwards 

 closely over the achenium, gibbous and compressed at the sides, (sometimes 

 rostrate,) tomentose. Achenium obovate, flatly compressed, naked, without 

 pappus, and deciduous with the bractes. — Small annuals of Europe and 

 North America, arachnoidly tomentose, resembling Filago or Gnaphalium. 

 Leaves alternate, capituli clustered. The presence of an involucrum, and 

 the supposed involucrum being bractes, this genus approaches Evax. 



§ III. * Rhyncholepis. — Involucrum Jive-leaved, paleaceous, fructiferous scales 



rostrate, rvith chaffy points. 



Micropus *angustifolius; Q erect, simple or branching from the base, tall and 

 slender, tomentose; leaves linear, acute, above linear-lanceolate; clusters of 

 flowers lateral and terminal, densely lanuginous ; discal florets about five, mas- 

 culine three to five. 



Hab. St, Barbara, Upper California. Six to eight inches high, leaves erect and somewhat 

 crowded, about an inch long and a line wide. Stem often simple. The capituli like dense, round 

 masses of wool. Female florets almost obsolete. Stigma scarcely exserted. Achenium smooth 

 and compressed. 



