CACTACER. 45 
4—6 robustos breves cinereos obscuros singulumque centralem breviorem obscuriorem gerentibus, 
in caule superiore florifero confertis lanam cinerascentem aculeosque 15-25 setiformes elongatos 
flexuosos angulosos rubello cinereos declinatos et quasi pendulos ferentibus ; floribus in acule- 
orum barba pene occultis carneis; tubo gracili supra ovarium globosum 10-squamatum con- 
stricto decurvo intus basi nudo sepalis 10-12 lanceolatis instructo; petalis 10-12 oblongis 
obtusiusculis ; stigmatibus 5-6 fasciculatis ; bacca parva globosa squamosa pulposa coccinea 
floris rudimentis coronata ; seminibus oblique obovatis carinatis levissimis lucidis, hilo angusto 
subventrali; albumine parcissimo ; embryone hamato cotyledonibus curvatis foliaceis incum- 
bentibus seu subinde obliquis. (Tab. LXXIV, fig. 16.) 
Sierra di Sonoyita, and southeast towards Santa Magdalena, Sonora, where it is named 
Zina, or Sina, or Sinita by the inhabitants, Schott: in August with flower and ripe fruit, 
—Stems 8-10 or more from the same base ; 8-10 feet high, ascending at base, and, when full 
grown, always curved outward at the top, the reverse of C. Thurberi ; often many plants 
together, forming thickets, and covering a large space of ground ; not rarely associated with 
the just-mentioned species. Stems of 2-4 articulations of 4 or 5 inches diameter ; lower part 
entirely denudated of the quite deciduous spines. Spines of the sterile joints, or young plants, 
| 5-7, not over 3 or 4 lines long ; areole of the flowering joints 3 lines in diameter, covered 
with a dirty whitish tomentum, 2-3 lines apart; spines irregularly fasciculated, 10-25 in 
number, and from 1 to 4 inches long, flexuous and pendulous. Flower somewhat hidden in 
this reddish-grey beard, and its tube evidently bent downward by it; length of flower 14-1} 
inch ; sepals without any wool in the axils, olivaceous; lower ones triangular, acute; upper 
ones lanceolate ; petals dirty flesh-color ; stamina comparatively few, leaving the top of the 
ovary and the lower part of the tube naked; stigmata 5-6, filiform, broom-shaped, exactly like 
those of CO. giganteus or C. Thurberi. Berry scarlet, 3 or 4 lines in diameter ; Seeds very simil 
to those of C. giganteus, but larger, 1.0-1.2 line long ; germination very much like that * 
the last two species; cotyledons of seedling plant acute, short, spreading ; head globose, but 
soon somewhat elongated, while both others remain globose for a long time. C. Schottii is 
closely allied to Pilocereus scoparius, Poselg. from Vera Cruz. This, however, is a larger plant, 
20-25 feet high, 1 foot in diameter, with 12-15 ribs on the sterile, and 20-25 on the flower- 
ing part. I have named this interesting species, the only Pilocereus of our Flora, after its 
zealous discoverer, whom I have often had occasion to mention in. these pages, and who, with 
all his other arduous duties in the field, still found leisure and inclination to study the Botany 
of the boundary from the Pacific to the Gulf of Mexico. 
IV. OPUNTIA, Tourn., Mill.* 
Subgen. 1. Srenopuntra. 
Articuli complanati. Aculei non vaginati. 
Flores parvi. Petala parva, subulata, erectiuscula (aurantiaca). 
Stigmata pauca (1-3), acuta. 
Bacca? et Semina ? 
* Besides its strictly differential characters (viz: the rotat lla and the flat bony seeds with large foli tyledons) this 
genus is distinguished from the other Cactacee by its subterete, subulate and deciduous leaves, and by its barbed spines, which 
I do not find in any other plant of thisfamily. These spines render Opuntia so much more disagreeable and even dangerous 
than other Cacti; in several species ( 0. fragilis, O. Bigelovii, O. Jrutescens and others) the joints easily separate from the stemand 
adhere by their barbed spines to the skin or clothes of the passer-by, the most annoying burs. Besides these spines which are 
* 
