TRANS. OF THE ACAD. OF SCIENCE. 
thus * the Mexican E. horripilus y Lera., and perhaps the South 
American E. Odieriiy Lem., and E. Cummingii, Salm, this 
species forms a small section of Echinocacti with the appear¬ 
ance of Mamillariae, named by Prince Salm, (Hort. Dyck., 
1849, p. 84,) Theloidei. Through the Ooryphanthce they are 
nearly allied to Mamillaria, while our species at least, (the 
fructification of the others not being known,) by its dry fruit, 
its black tuberculated seeds, and especially the large, and 
curved embryo and the presence of an albumen,, proves itself 
a true Echinocactus, very closely connected with the regu¬ 
larly ribbed E. intertextus, Eng. Cact., Mex. Bound, t. 34. 
The similarity in all essential organs of these two species is 
such that no system ought to separate them, proving again of 
how little essential importance among Cactaceae the external 
form must be regarded; another striking example, among 
many, is the rat-tail Cereus tuberosus , and its globular or oval 
allies, C. cazspitosus, etc. 
Full grown specimens are 3-5 inches high and 3-4 inches 
in diameter; dark green tubercles, loosely arranged in -g T or 
Af order, 8 and 13 spirals being most prominent; tubercles 
6-8 lines long, at base 6—7 1. wide in the vertical and 4—5 1. 
in the transverse diameter, fruit-bearing ones rather shorter 
and stouter; areolae 3-4 1. long; external spines 4-6 1. long, 
whitish, with the addition of several bristles at the upper end 
of the areola; central spines 5-7 1. long, yellow, reddish, deep 
brown, or even black, upwards. Flowers 8-10 1. long, and of 
nearly the same diameter, with a short and wide tube, exter¬ 
nally greenish purple, petals yellowish-green verging to pale 
purple; the short stamens arise from the whole inner surface; 
of the tube, leaving only a very small nectariferous space in 
its base; funiculus very short, stout and straight, and not 
curved over the micropyle, as I have found it in almost all 
other cactus flowers examined. Fruit 3-3^ 1. long, about the 
same in width, with 1-3 small calycine scales towards its flat 
top, each with 1 or 2 small spines in its axil; it usually bursts 
irregularly on the side, and, falling off, leaves its base adher¬ 
ing to the areola, as is the case in other dry-fruited Echino¬ 
cacti ; e. g. E. korizonthalonius. Seeds lh 1 . long in the 
longest diameter, covered with minute closely set tubercles, 
with a large oval subbasilar hilum, and an embryo strongly 
curved around a small albumen. The plant germinates with 
* Mamillaria papyracantha^ng. PI. Fendl., p, 49; Syn. Cact.,p. 8. A 
closer examination of the dry specimen obtained by Mr. Fendler near 
Santa Fe proves that the floral areola joins the spiniferous one on the top 
of the small nascent tubercles, making the plant an Echinocactus, accord¬ 
ing to the views at present prevalent. It is singular that Fendler’s single 
specimen has remained, thus far, the only one ever obtained of this well 
marked species. 
