84 WILLIAM TRELEASE ON THE 



Our species of Erodium, including those which have become naturalized or are merely 

 occasional ballast-plants, belong to the section with the arched upper half of the awn 

 naked or at most short-pubescent; but in another section, represented by E. glaucophijl- 

 lum and several other species, this appendage is much elongated, and plumose with a 

 double series of long silken hairs. There can be little doubt that the carpels of species 

 of this section are carried about freely by the wind, while they may at length be planted 

 by the coiling and uncoiling of the lower part of the awn, as in the species already de- 

 scribed. This may also be expedited by the action of the wind upon the plumed awn, 

 after the fruit has once caught in tlie soil, as I have convinced myself by grasping the 

 ovary between my thumb and finger, and Ijlowing irregularly upon the plume; the re- 

 sult in every instance being to crowd the ovary down several milHmeters in a short 

 time. (Note 7.) Here again it is interesting to observe an identical conti-ivance in 

 Sti'pa pennata and related species, which differ from others of the genus in possessing a 

 long-plumed awn.^ Monsonia, a close relative of Erodium, likewise inchides species 

 with plumed and plumeless fruit. 



LIMNANTIIEAE. 



Flowers regular, very slightly perigynous, 3-5-merous, homogone; sepals valvate, 

 persistent and somewhat enlarged in fruit; petals convolute or open, withering-persist- 

 ent; stamens twice as many as the sepals, all Avith anthers; glands opposite the sepals, 

 evident; carpels opposite the sejials, their 1-ovnled ovaries distinct, the style rising from 

 the centre; fruit a series of semi-drupaceous rugose-tubereulate nutlets. — Llmnantha- 

 ceae of continental writers ; two genera, exclusively IsTorth American. 



LIMNANTHES, R. Br., Loiulon ;ind Ediiih. Pliilos. Mag., n, 70;Boiith. and Hook., Geii., i, 274. 



Rather succulent annual herbs with alternate once to thrice pinnately dissected peti- 

 oled mostly estipulate leaves; flowers solitary at the ends of bractless axillary peduncles, 

 4- or mostly 5-merous; petals obovate-cnneate, mostly emarginate, convolute; filaments 

 distinct, somewhat dilated at base, their tips at first recurved outwards; anthers at length 

 introrse; style about equalling the stamens; seed exalbuminous, closely invested by the 

 pericarp; embryo straight, with plane cotyledons. Eloerkea, Baillon, Adansonia, x, 362; 

 Hist, des PL, v, 20, in part. — ^Four species, confined to the Pacific slope. 



1. L. ALBA, Hartweg, Benth., PI. Hartw., 301. A span or two high; yonng leaves and 

 flowei'-bnds very white-lanose ; leaves remotely 5-9-divided, the divisions linear-oval, 

 mostly 10-15 mm. long, entire, 3-lobed or trifid; sepals ovate-lanceolate, acute or acumi- 

 nate; j)etals pale yellow or white, emarginate or truncate, 10-12 mm. long; stamens about 



' The experiments of Mr. Parker witli this grass (wbicli tliis force alone is sufficient to bury the grain completely 



consisted in Ijarely starting tlie point of the fruit in loose in sanily soil within twenty-four hours, while the hygro- 



eartli, anil placing it where tlie air from a sliglitly opened scopic action of the lower part of the awn is also efficient, 



window blew upon it iutermitteully) demonstrated that See, further, Lubbocli, Kept. Brit. Assoc. 1881, 6G8. 



