2 
2 West AMERICAN SCIENTIST- 
ists alike, and neither the “law of priority,” nor the rule, “once a synonym 
always a synonym,” should be made retroactive in a case like this. 
M. aGGREGATA Engelmann, in Emory’s Rec. 157, f. 1. 1848. 
Original description: —“October 18, 1846; head waters of the Gila, 
6,000 feet above the sea. Proliferous in the highest degree, forming hem- 
ispherical masses often of a diameter of 314°; which are composed of 1o0— 
200 different heads or stems. Single heads conical, apparently 4 or 5 
high, and 24-3’ in diameter; color, bluish green; spines white or reddish. 
This species appears to be allied to M. vivipara, but is distinguished by 
the conical heads, and the hemispherical tufts, while M. vivipara has hem- 
ispherical or even depressed heads, and forms flat and spreading masses- 
e an undescribed species, in which case the name of M. aggrega- 
ta appears to be most appropriate.” Engelmann, L. c. 
Engelmann, in Ives’ report,and Watson, in his Bibliogr. Index, re- 
fer this to Cereus phceniceus. Coulter makes it Cereus aggregatus in 
his “Revision.” Perhaps a form of C. polyacanthus, but it may have 
been any one of half | a dozen Tepe so far as our positive knowledge ex- 
tends, hence we cons i wise to attempt to revive the name at the 
expense of diskette a 5 al stich name. 
M. ALVERSONI Hort. 
Cactus radiosus alyersoni Coulter:—“Differs from var. deserti in its more 
robust and branching habit (becoming 12.5 cm. tall and 10 em. in diam- 
eter), shorter and thicker tubercles, more numerous (12-14 centrals) 
-stouter and longer (12-22 mm.) spines, all of which are black-tipped (the 
centrals black half way down, shading into red), and pink flowers. In 
the desert region of extreme southeastern California. ‘Fox-tail cactus.’ 
Selected specimen plants alone answer the above description; Mr. A- 
_H. Alverson, who collects this form on the Mohave desert, and in whose > 
honor it is named, has shown me specimens with spines whihe throughout, 
d an examination of a large series of plants has convinced me of the 
identity of this with M. deserti, M. arizonica, ete. 
M. APPLANATA Engelmann, Boston Journal of Nat’l History, vi. 198. 1850- 
Original description:—“Simplex, depressa; tuberculis clongato-pyt- 
amidatis subquadrangulatis apice ex tomento albo lanoso dem nes- 
cente aculeiferis; aculeis rectis 15-20 tenuioribus inaequalibus radiantibus, 
os me centrali robustiori erecto; axillis nudis; floribus sordide albidis  s. 
His; hurl cana sepalis 8-13 lanceolatis; petalis 12-18 lanceolatis 
