290 MESSRS. W. WEST AND G. S. WEST ON 
Long. 48 u; lat. 30 p; lat. apic. 17 p; lat. isthm. 8 p; crass. 19 p. 
Hab. De Land, Florida. 
53. Evastrum EVOLUTUM, West & G. S. West, in Trans. Linn. 
Soc. Ser. II. (Bot.) v. p. 243, pl. 14. f. 22 (1896).—E. abruptum, 
Nordst., var. evolutum, Nordst. in Ofvers. Sv. Vet.-Akad. Forh. 
(1877), no. 3, p. 21, t. 2. f. 7..—E. Nordstedtianum, Wolle, Desn. 
U. S. pp. 105-6, pl. 26. ff. 7, 9-12 (1884). — E. coronatum, 
W. B. Turn. in Journ. Roy. Mier. Soc. Ser. ll. v. pp. 935-6, 
pl. 15. f. 9 (1885). 
E. mediocre, circiter 14-plo longius quam latum, profunde 
constrictum, sinu lineari extremo subampliato ; semicellule 
suboblonge vel pyramidato-trapeziformes, 5-lobe, incisuris 
lateralibus similibus apertis et rotundatis; lobis lateralibus 
et basalibus similibus, subrotundatis vel subtruncatis, inferi- 
oribus paullo majoribus, spinis brevibus validis 3 (sæpe 2 
vel 4) ad marginem et spina singula (vel rarius spinis binis) 
intra marginem; lobo polari maximo, late oblongo et truncato, 
lateribus rotundatis cum spinis brevibus plerumque 2, angulis 
apicalibus cum spina singula valida divergenti (longitudinis 
variabilis) instructis, incisura mediana profunda et subaperta, 
intra marginem apicalem cum verruca rotundata, emarginata vel 
bidentieulata juxta ineisuram apicalem utrobique: in centro 
semicellularum verruca magna subtrilobata, juxta ged supra 
verrucam cum serobiculis magnis binis, intra angules inferiores 
et juxta sinum cum granulo magno singulo (vel verruca emargl- 
nata); a latere vise angulari-ovate, basin versus cum verrucà 
magna emarginata utrobique, angulis superioribus emarginatis, 
in medio apicis cum dente instructa; a vertice vis® elliptic®, 
polis denticulatis, in medio utrobique cum  verruca magna 
emarginata. 
Long. 60-71 p; lat. 37-47 u; lat. isthm. 105-15 p; lat. 10b. 
polar. 30-35 p ; crass. 27:5-31 p. (Fig. xylogr. 14 et b.) 
Hab. Minneapolis, Minnesota; Scarbro', Maine; fc. — f 
This species, originally described from Brazil as a variety ° 
E. abruptum and since found in S. Africa (cf Nordstedt, à 
Act. Univers. Lund. vol. xvi. (1880), p. 10), is a frequent Xo"! 
American species of Euastrum; and after examining bunre s 
of specimens from many parts of the United States, we i 
become well acquainted with its various forms. For an accon it 
of its distinctive peculiarities vide West & G. S. West, |. ud 
is a very distinct plant from E. abruptum, à figure of a sm 
form of which we give for comparison (PI. 16. fig. 10). 
