ROBINSON AND GUKENMAN. — MEXICAN PLANTS. 51 



white wool : leaves all radical, ruuciuately pinnatifid, glabrous or nearly 

 so, petioled, thin, acutish ; lobes 5 to 7, luucronulate-dentate : stems 

 about a foot high, slender, dark colored, quite smooth, bearing a lew 

 scattered minute oppressed subulate bracts and at the summit 2 or 3 

 heads on slender ascendinjr branches: heads 9 lines lonij, about 18- 

 flowered : scales of the involucre in 5 series, obtuse, flattish (not thick- 

 ened nor firm in texture), dark colored, ciliated, otherwise glabrous, the 

 inner ones 5 lines long: flowers lilac in dried state, 7 to 8 lines long (in- 

 cluding the achenes). — Collected by C. G. Pringle, in shade, at Tomellin 

 Canon, Oaxaca, altitude 3,000 feet, 1 December, 1895, no. 5966, Closely 

 related to P. nudicauUs, Gray, but having a more numerously seriate in- 

 volucre with thinner flatter scales, and flowers nearly twice as large. 



SONCHUS ASPEK, Vill. Although so generally distributed as a weed 

 upon waste heaps, etc., this plant does not appear to have been noted 

 in Mexican lists. It has been collected at San Diego, Chihuahua, by 

 Hartman, and near the city of Oaxaca, by Nelson, no, 1353. 



