140 Plants Collected in Paraguay. 



streams running from the Cordilleras to the Paraguay are brackish 

 or strongly impregnated with salt. 



Erigeron Bonariense, L., Sp. PL, 863. 



Gran Chaco near Asuncion (359). December-January. 



It is difficult to see any difference between this species and a 

 Conyza, as there is really no ligule on the ray flowers, or it is so 

 minute as to be inappreciable. A tall coarse weed 12-15 dm. high, 

 with a very large head of branches, some 5-Y dm. long, springing 

 from nearly the same point. Heads small, apparently discoid, the 

 flowers all threadlike, tubular and fertile. Flowers and pappus 

 tawny. Stem stout, striate, rough on the striae, pubescent among 

 the inflorescence. Leaves linear, glabrous, serrulate, 6-12 cm. long. 

 Common in the lowlands on the western side of the Paraguay. 



Erigeron linifoliiis, Willd., Sp. PL, iii, 1955. 

 Conyza pleheja, PliiL in Herb. Kew. 

 Conyza ambigua, D.C., Prod., v, 381. 



La Plata, Arg. Republic (22); Asuncion (322 and 342). October- 

 December. 



Stems 3-9 dm, high, hirsute, branching. Flowers white. Kay 

 flowers nearly or quite without ligules. Pappus tawny. Peduncles 

 and scales hirsute. Leaves linear, sparsely serrate, 5-Y cm, long, 

 1 mm. wide. Difi'ers from the preceding species also in the lower, 

 more stragglingly branched stems, and larger heads. 



Conyza Cllilensis^ Spreng., Nov. Prov., 1818, p. 14. 



Luque (343); Asuncion (628); Pilcomayo River (1514). Decem- 

 ber-January. 



Heads much larger than in either of the 2 preceding species, 

 1-lJ cm. high, 1 cm. broad. Stems striate, and with the leaves and 

 peduncles closely white hirsute, 7-10 dm. high. Leaves oblong- 

 linear or obovate, more or less serrate and scabrous on both sides, 

 4-8 cm. long and 5 mm. to 2^ cm. wide, the lowest usually obovate, 

 the uppermost linear. Ray flow^ers without ligules. Heads in small 

 terminal corymbs, 20 or less in number. 



Conyza triplinervia, Less., Linnsea, 1831, p. 137. 



Yilla Rica (497). January. 



A suS"ruticose, glabrous species, 3-6 dm. high. Heads small, in 

 large terminal panicled corymbs. Stems and leaves more or less 



