522 BLAKE. 



utrinique acuminata longe petiolata subintegra cavilina 3-4 (infra 

 mediam partem caulis). Capitula majuscula longe pedunculata, 

 pedunculis basi unibracteatis. Flores radii ca. 10 flavi, disci numerosi 

 flavi. — Species unica Hclianfhella madrensis Wats. 



PiONOCARPus madrensis (Wats.) Blake, n. comb. — Helianthella 

 madrensis Wats.! Proc. Am. Acad, xxiii. 278 (1888). — Chihuahua: 

 pine plains, base of the Sierra Madre, 19 Sept. 1887, Pringle 1302 

 (type coll.: Kew). 



The genus Pionocarpus (inchu, fat, and Kapirbs, fruit) is distinguished 

 from Helianthella chiefly by characters of the achene and style. The 

 achenes of Pionocarjnis are strongly thickened, unmargined, and 

 broadly truncate at apex, and the style-branches bear a long hirtellous 

 appendage. In Helianthella, on the contrary, the achenes are very 

 flatly compressed, as in Encelia, are more or less distinctly white- 

 margined, and at the true apex are much narrower than the body, 

 the more or less united squamellae being borne in a notch at the sum- 

 mit of the achene between the two awns. From Phoebanthus, to 

 which its relationship is rather closer, Pionocarpus is separated by its 

 habit and by the much more conspicuous squamellae. 



Perymenium blepharolepis Blake, n. sp. Frutex ramosus. Cau- 

 lis densissime strigillosus cortice cano-brunneo tectus aetate glabratus; 

 rami tenues subquadrangulares strigillosi fusco-brunnei. Folia oppo- 

 sita ovata subacuminata basi cuneata vel cuneato-rotundata trinervia 

 appresse serrata (dentibus 7-8-jugis) supra viridia strigillosa pilis 

 basi tuberculatis subtus pallidiora non canescentia strigosa et strigil- 

 losa plus minusve glanduloso-adspersa 2.5-3.8 cm. longa 10-17.5 mm. 

 lata. Petioli tuberculato-strigosi 2 mm. longi. Capitula 1.5-2 cm. 

 lata in apicibus ramorum 5-7 sublaxe cymoso-paniculata in pedun- 

 culis axillaribus et terminalibus strigillosis 1.2-4.5 cm. longis. Discus 

 7-9.5 mm. altus 6-8 mm. crassus. Involucri 3-sub-4-seriati gra- 

 dati 7 mm. alti squamae exteriores ovatae interiores ovato-lanceo- 

 latae plus minusve strigillosae et ciliatae infra subinduratae pallidae 

 ca. 5-nerviae apice laxo angustato subacuto herbaceo. Radii 8 fer- 

 tiles aurei oblongo-ovales bidenticulati in venis dorso plus minusve 

 puberuli 7-5 mm. longi 3 mm. lati. CoroUae disci aui'eae in dentibus 

 hirtellae 4.8-5 mm. longae (tubo 1.4-1.5 mm.). Paleae obtusae su- 

 pra strigillosae in margine et carina spinuloso-ciliolatae 5.8-7 mm. 

 longae. Achaenia juventate plus minusve piloso-hispida maturita- 

 tem vergentia sparse hispidula. Pappi aristae ca. 12 caducae ad 

 1.3 mm. longae subaequales (2 longioribus 3 mm. longis exceptis). — 

 Puebla: Coxcatlan, alt. 2135-2440 m., Sept. 1909, Pnrpus 4143 



