396 COMPOSITE. Perityle. 



Moist ground, from San Francisco Bay to San Diego. Scales of the involucre sometimes tipped 

 with purple. Rays 2 or 3 lines long. The minute papillae on the akene, as seen under the 

 microscope, swell up when wetted, open at the extremity or split into two valves, and emit two 

 long filaments of extreme tenuity, the whole apparently forming a gelatinous mass enveloping the 

 akene ; just as occurs in Croddium and in some species of Scnecio, &c. From this peculiarity it 

 took its generic name, which means "mucilaginous seed." 



CIIOCIDIUM MULTICAULE, Hook., is a small plant resembling Blcnnospcrma, but with a fuga- 

 cious capillary pappus. It is common along the coast of Oregon, but has not been detected in 

 California ; the specimen so named in the Botany of the Mexican Boundary, collected by Dr. 

 Stillman, proving to be Blcnnospcrma. See Proc. Am. Acad, ix. 206. 



84. PERITYLE, Benth. 



Head many-flowered, with pistillate rays or occasionally none ; the flowers all 

 fertile. Involucre campanulate, of nearly equal scales, slightly carinate on the 

 back, in a single or double series. Eeceptacle flattish or conical, naked. Rays 3- 

 toothed : disk-corollas 4-toothed ; the tube glandular. Style-branches tipped with 

 (or insensibly changing into) a short and obtuse or more commonly subulate or 

 filiform, hairy appendage. Akenes oblong, flat (laterally compressed), dark-colored, 

 bordered by a cartilaginous mostly ciliate- bearded margin. Pappus a series of 

 hyaline or setiform scales, usually more or less united into a cup or crown, and 

 commonly a slender awn from one or both margins. Low annuals or perennials, 

 of the southern part of California and adjacent regions ; with petioled usually 

 palmately-lobed or incised and membranaceous leaves, at least the lower ones oppo- 

 site, and pedunculate rather small heads terminating corymbose or paniculate 

 branches (rarely in a corymbose cyme). Rays white (or sometimes yellow 1) : disk- 

 flowers yellow. Benth. Bot. Sulph. 23, t. 15, & Gen. PI. ii. 398; Gray, Proc. 

 Am. Acad. ix. 194. 



In our view, as stated in the paper above cited, the crown of pappus furnishes a better character 

 than the style-appendages, or anything in the involucre, to distinguish this genus from Lap- 

 hainia, one species of which also has short a.nd blunt style-appendages. Laphamm nearly takes 

 the place of Perityle eastward, and one sp'ecies of it inhabits the southern part of Nevada. 



P. IXCANA, Gray, Proc. Am. Acad. ined., recently discovered on Guadalupe Island, Lower 

 California, is an anomalous species, stout and somewhat frutescent, as white-woolly as Scnccio 

 Cineraria, and with numerous rayless heads in a crowded and naked pedunculate corymb. 



1. P. California a, Benth. Pubescent or glabrate : leaves mostly opposite, 

 broadly ovate or deltoid, incisely toothed or somewhat lobed : rays oblong, perhaps 

 yellow : style-appendages short and obtuse : akenes hispid-ciliate : the outermost 

 obovate and with much thickened corky-cartilaginous margins, the inner obovate- 

 oblong and with nerve-like margins, narrowed at the top : awns of the pappus one 

 or two, scabrous. 



Probably only in Lower California; Bay of Magdalena, Hinds; Cape San Lucas, Xantus. 

 Heads 3 or 4 lines long. Throat, i. e. the expanded upper part, of the disk-corolla, rather shorter 

 than its tube. Receptacle almost flat. 



2. P. plumigera, Gray. Glandular-puberulent above, the base of stem un- 

 known : leaves of the branches ovate or oblong, small, toothed : heads smaller than 

 in the foregoing : rays oblong, apparently white : style-appendages short and obtuse : 

 akenes oblong, not contracted at the apex, very densely villous-ciliate : awn of the 

 pappus only one, nearly equalling the corolla, sparsely hispid-plumose above. PL 

 Fendl. 77. 



California, Coulter. Probably from the southeastern borders of the State or adjacent portion 

 of Arizona. Receptacle strongly convex. 



3. P. Acmella, Gray, 1. c. Puberulent and somewhat glandular : lower leaves 

 opposite, ovate and deeply 3-cleft ; the upper alternate and somewhat hastately 



