HOMALOCEPHALA. 
181 
Echinocactus subgrandicornis Haage (Forster, Handb. Cact. 347. 1846) is only a name. 
Echinocactus thelephorus (Hortus in Forbes, Journ. Hort. Tour Germ. 152. 1837) is 
very briefly described and we can not identify the plant. 
Echinocactus verutum (Forster, Handb. Cact. 344. 1846), from Mendoza, was once 
grown in English gardens. It is only a name. 
Echinocactus villiferus Scheidweiler (Forster, Handb. Cact. 347. 1846) is only a name. 
Echinocactus wilhelmii is listed by Schumann (Monatsschr. Kakteenk. 5: 108. 1895) as 
from Hildmann’s Catalogue. 
20 . HOMALOCEPHALA gen. nov. 
Low, depressed or subglobose plants, strongly ribbed; spines stout; flowers central, rather large, 
day-blooming; outer perianth-segments very narrow, pungent; inner perianth-segments narrow, 
widely spreading; ovary covered with numerous linear pungent scales bearing in their axils masses 
of white wool; fruit globular, scarlet, becoming naked, at first juicy, bursting irregularly; seeds large, 
black, smooth, reniform. 
The generic name is from o/mAos level, 
and Kecf)a\ri head, referring to the depressed 
plant body. 
We recognize only one species, first 
published as Echinocactus texensis Hopffer. 
1. Homalocephala texensis (Hopffer). 
Echinocactus texensis Hopffer, Allg. Gar- 
tenz. 10: 297. 1842. 
Echinocactus lindheimeri Engelmann, Bost. 
Journ. Nat. Hist. 5: 246. 1845. 
Echinocactus plalycephalus Miihlenpfordt, 
Allg. Gartenz. 16: 9. 1848. 
Echiyiocaclus texensis gourgensii Cels in 
Labouret, Monogr. Cact. 196. 1853. 
Echinocactus texensis longispinus Schelle, 
Handb. Kakteenk. 161. 1907. 
Usually simple, sometimes globose, but generally much depressed, in large plants 30 cm. broad, 
10 to 15 cm. high; ribs 13 to 27, very prominent, acute; areoles only 2 to 6 to a rib, densely white- 
felted when young, large; radial spines usually 6, rarely 7, spreading or recurved, more or less flat¬ 
tened, unequal, 1.2 to 4 cm. long, or rarely 5 cm. long, reddish, more or less annulated; central spine 
solitary, longer than the radials, 3 to 6.5 cm. long, 3 to 8 mm. broad, much flattened, strongly annu¬ 
late; flowers broadly campanulate, 5 to 6 cm. long and fully as broad, scarlet and (Tange below, pink 
to nearly white above; outer perianth-segments linear with more or less lacerate margins and ter¬ 
minated by long spinose tips; inner perianth-segments with less pungent tip or without any, but 
with strongly lacerate margins; filaments red; stigma-lobes 10, linear, pale pink; scales on the ovary 
and flower-tube linear, pungent; fruit scarlet, globular, 16 to 40 mm. in diameter, nearly smooth 
when mature, at first pulpy but becoming dry and apparently splitting open unequally; seeds large, 
uniform, black, smooth, shining, somewhat flattened, angled on the back, 3 mm. broad; hilum lateral, 
large, depressed; “embryo curved or hooked with the foliaceous cotyledons buried in the large 
albumen” (Engelmann). 
Type locality: Texas; type grown in a botanical garden from seed. 
Distribution: Southeastern New Mexico, Texas, and northern Mexico. 
The flowers of this species open for four days in bright sunlight, closing at night; they 
are delicately fragrant. 
This plant shows great variation in the size of the fruit and in the way it ripens and 
dehisces the seeds. In 1921 Mr. Robert Runyon sent us a box of very large fruits, almost 
twice as large as any previously studied; none of these fruits split open as it ripened. 
Dr. C. R. Ball writes of this plant as follows: “This plant is extremely abundant on 
the high plains of western and northern Texas. In establishing farms in this section large 
