524 BLAKE. 



Discus 5-7 mm. altus 4-6 mm. crassus. Involucri 3-seriati 4 mm. 

 alti paullum gradati squamae extimae breviores late ovatae obtusae 

 strigillosae vix ciliolatae basi coriaceo-induratae apice herbaceae 

 mediae et intimae late oblongae subobtusae minus induratae ciliola- 

 tae et strigillosae apice subherbaceae. Radii 8 fertiles flavi ovales 

 bidenticulati dorso glanduloso-puberuli 4.5-5.8 mm. longi 2.8 mm. lati. 

 CoroUae disci flavae in tubo puberulae 3-4.2 mm. longae (tubo 0.6-1.6 

 mm.), faucibus valde ampliatis. Paleae subacutae scariosae flavae in 

 carina hispidulae margins superne lacerato-dentatae 4.2-4.6 mm. 

 longae. Achaenia brunneo-nigrescentia transverse plus minus ve 

 rugulosa incrassata submarginata apice rotundata sparse strigillosa 

 1.8 mm. longa 1 mm. lata. Pappus fragilissimus ex aristis 2 tenuibus 

 spinulosis 2.5 mm. longis et aristulis ca. 12 inaequalibus (longiori- 

 bus ad 1 mm. longis) compositus. — Guatemala: shrubby growth, 

 alt. 1311 m., near Coban, Jan. 1879, von Ttierckheim. 339 (type coll.: 

 British Museum, Kew). — This number is referred in Robinson & 

 Greenman's revision (Proc. Am. Acad, xxxiv. 526 (1899)) to P. gymno- 

 lomioides (Less.) DC, originally described from Vera Cruz, but differs 

 in several important features from the description there given of that 

 species, which is said to have entire leaves, 3-5-headed corymbs, 

 spreading-pubescent pedicels, and much shorter petioles (3 mm. long). 

 Chrysactinia acerosa Blake, n. sp. Frutex ramosus pedalis. 

 Caulis tenuis brunneo-griseus minute hirtellus aetate glabratus oppo- 

 site ramosus. Folia opposita vel superiora alterna filiformi-subulata 

 2-4-glanduloso-punctata semiteretia supra complanata apice subulato- 

 mucronata glabra laete viridia 6-8 mm. longa 0.25 mm. lata saepius 

 ramulos brevissimos foliosissimos subtendentia. Pedunculi ramos 

 terminantes monocephali glandulari-hirtelli lineari-subulato-bracteo- 

 lati striati ad 1 cm. longi. Capitula (immatura) hemisphaerica 5-6 

 mm. alta. Involucri uniseriati 3.5 mm. alti squamae aequales 8 

 anguste oblongae (0.8-1.3 mm. latae) membranaceo-chartaceae viri- 

 descentes obtusae subcarinatae in margine scarioso sparse eroso- 

 ciliatae infra apicem glandula anguste oblonga brunnea praeditae. 

 Radii (immaturi) aurei oblongi fertiles. Corollae disci (immaturae) 

 aureae in dentibus minute hirtellae 4 mm. longae. Achaenia (imma- 

 turissima) pubescentia. Aristae pappi ca. 24 tenues spinulosae 

 subaequales ad 3.5 mm. longae. — San Luis Potosi: Sierra de Guas- 

 cama, Minas de San Rafael, June 1911, Purpus 5136 (type coll.: 

 British Museum, Gray Herb., U. S. Nat. Herb.). — Distributed as a 

 narrow-leaved form of C. mexicana Gray, but seemingly quite distinct 

 from that species in foliar and involucral characters. 



