nothing of its laterally llatteJied carpels, yellow flowers, and general habit. 
It seems to coincide in characters most Avith Velcca, but is at \miance in 
the most important character in that genus, viz; a strongly involute seed, 
enclosing a central cavity. Almost identical in habit with Mtisenhim, its 
carpels are flattened laterally instead of dorsaiiy, the seed-face is not so 
broadly but more deeply concave, the intermediate ribs (like Velwa) are 
much nearer the dorsal than the laterals, instead of being equidistant, its 
oil-tubes are more uniform in size, and its calyx-teeth are obsolete. It also 
simulates Aletes acaulin in general appearance, but differs radically in 
fruit structure. Such a combination of resemblances and differences can 
best be expressed by an independent genus, and hence we use Gray’s 
section name under TauHchia and raise it to generic rank. 
1. M. Texana. Acaulescent: scape 2 to 8 inches high, 
lonoer than the leaves, somewhat scabrous at base of umbels: 
leaves 5 to 7-pinnate; lower pinna; petiolulate, pinnately parted; 
segments cuneiform, 3 to 5-cleft: umbel 5 to 8-rayed: fruit 
lines long. (Fig, 141.) — l^auschia I'exana Gray, PI. Lindh. ii. 
211. Etdo'phtis 7'exanus Benth. & Hook. Gen. Plant, i. 885. 
Western Texas, and extending into Mexico, FI. July. 
44. CONIUM Linn. Gen. n. 386. — Poisonous biennials, 
with spotted stems, large decompond leaves with lanceolate pin* 
natifid leaflets, involucre and involucels of narrow bracts, and 
white flowers. 
C. MacUlatum L. a large branching European herb, in 
waste places throughout the northeastern states and Canada; also 
found in California. FI. July. (Fig. 142. ) 
45. SIUM Linn. Gen. n. 348. — Smooth perennials grov/ing 
in water or wet places, with pinnate leaves and serrate or pinnatifid 
leaflets, involucre and involucels of numerous narrow bracts, and 
white flowers. 
Bentham & Hooker refer our two species of Sium to Apiiim; but they 
seem abundantly distinct, as indicated by Watson, Bot. Calif, i. 261 . The 
oil-tubes are never solitary in all the intervals, and the prominent grou p 
of strengthening cells in the outer edge of each rib, as well as the broad 
intervals, still further emphasizes the distinction. There is no better de- 
fined generic group than that formed by our two species of Sium, being so 
nearly identical in fruit and so easily separated from all other g enera. 
1. S. cicutaefolium Gmelin. Syst. ii. 482. Stout, 2 to 6 
feet high: le.aflets 3 to 8 pairs, linear to lanceolate, sharply serrate 
