BLAKE—REVISION OF TITHONIA. 435 
Sanvapor: San Salvador, 1905, Velasco (J. D. Smith, no. 8868) (G,N). Without 
definite locality, Renson 19 (N). 
Costa Rica: San Vicente, altitude 1,200 meters, 1888, Cooper (Pittier & Durand, 
no. 565; G, N). San José, 1889, Pittier 1442 (G); in 1893, Tonduz 7140 (G, 
N). San Francisco de Guadalupe, altitude 1,100 meters, 1895, Tonduz (J. D. 
Smith, no. 7066; G, N). Near Guadalupe, 1892, Tonduz 7186 (N). 
Jamatca: Introduced, Hope Grounds, altitude 210 meters, 1915, Harris 11877 (G). 
Ceyion: Trimen (G, K). 
Burma: “A plant which is becoming a pest in Burma,’’ 1912, Lace (K). 
Sprairs SETTLEMENTS: Singapore, 1861, 7. Anderson (K); in 1875, Kuntze 
607A (K). 
Cuumvatep: Mount Jackson, Fontabelle, Barbados, 1895, Waby 116 (K). 
Government House Grounds, Trinidad, 1909, Broadway 3605 (K). 
Tithonia diversifolia is easily distinguished from the other species of the genus by 
its large heads, broadly rounded phyllaries, and usually 3-lobed leaves. Itis described 
on some collectors’ labels as a shrub, but is more probably an herbaceous perennial. 
In spite of its widely different characters, it was treated by Otto Kuntze as a variety 
of T. rotundifolia (Urbanisol tagetifolius of Kuntze), with several forms of no real 
consequence. 
The species has become somewhat widely spread as a weed in Ceylon and parts of 
farther India. Trimen has noted on a sheet in the Kew Herbarium: “After Lantana, 
the commonest weed in Ceylon. Originally escaped from Peradeniya, where it is 
called ‘Verbesina.’” In his flora of Ceylon, he says:‘ ‘‘ Tithonia diversifolia, Gray, a 
native of Mexico and California, though only introduced as a garden plant so recently 
as 1851, is now one of the commonest and most conspicuous plants in the island, and 
is generally known as the ‘Wild Sunflower.’ It doubtless spread from Peradeniya, 
but is now completely established by roadsides and waste ground over the whole 
of the moist region up to 5,000 ft., and in places in the dry region also.’’ In Jamaica, 
Harris speaks of it as ‘‘introduced but now widely spreading in gardens and as an 
escape in waste places.’’ In Salvador, according to Renson and Velasco, it bears the 
vernacular names ‘‘jalacate” and ‘‘guasmara.’’ 
10a. Tithonia diversifolia glabriuscula Blake, subsp. nov. 
Stem essentially glabrous; leaves less pubescent above, very sparsely puberulous 
beneath, especially along the veins, and gland-dotted. 
Type in the United States National Herbarium, no. 256799, collected north of 
Tuxtepec, Oaxaca, Mexico, altitude 90 meters, April 9, 1894, by E. W. Nelson 
(no. 346). 
OTHER SPECIMENS EXAMINED: 
Veracruz: Tlacatalpam, 1894, Nelson 496 (N). Without definite locality, 
1910, Orcutt 3427 (N). 
Oaxaca: About Santo Domingo, altitude 275 meters, 1895, Nelson 2666 (G, N). 
Tolosa, 1898, Deam (G, N). 
Intermediates between this and the typical form are represented by Langlassé 
528, Gaumer 944, and Holway 526 and 701. 
EXCLUDED SPECIES. 
TiTHONIA ANGUSTIFOLIA Hook. & Arn. Bot. Beechey Voy. 435. 1841. 
This is Viguiera angustifolia (Hook. & Arn.) Blake.® 
TiTHONIA ARGOPHYLLA D. C. Eaton; S. Wats. in King, Geol. Expl. 40th Par. 5: 423. 
1871. 
This is Enceliopsis argophylla (D. C. Eaton) A. Nels. 
4 Hand-book Fl. Ceylon 3: 39. 1895. 5 Proc. Amer. Acad. 51: 518. 1916. 
