160 CACTACEA OF WHIPPLE’S EXPEDITION. 
dusky when young ; radial spines slightly bulbous at base; upper ones 2-5 lines, lateral ones 6-15 lines long, and 
lower ones hardly a little shorter ; central spines very bulbous; upper ones not much longer than the lower radial 
ones ; lower central spine sharply quadrangular, mostly compressed, often deflexed and curved, 1-3 inches long. 
On the San Francisco mountains a specimen was collected with 11 ribs, 8-9 radial spines (4~12 lines long), the 
uppermost shortest, and 3-4 reddish-gray central spines, very bulbous at base, the lowest longest (12-20 lines long) 
and angular. In superficial appearance this plant resembles C. Mojavensis ; but it must be referred here, and seems to 
indicate a range of this form through seven degrees of longitude. 
A specimen from Anton Chico, on the Pecos, seems to unite C. conoideus with C. pheniceus. Areole more 
distant than the latter ; spines longer ; 3 central spines, lower one somewhat curved and angular. Collected Sept. 28 
and Dec. 18, 1853. . 
‘10. C. ENGELMANNI, Parry, var. VARIEGATUS: ovato-cylindricus, simplex s. parce e basi ramosus, 12-costatus, 
areolis orbiculatis approximatis, aculeis exterioribus sub-13 gracilibus rigidis albis apice sphacelatis adpressis lateralibus 
longioribus, summis deficientibus ; aculeis centralibus 4 cruciatis (raro 5) plus minus curvatis infimo elongato angu- 
lato albo decurvato, ceteris brevioribus teretiusculis nigris corneisque variegatis ; floribus ex axillis areolarum vetus- 
tiorum inferiorum ; bacca ovata sicca pulvillis numerosis setas tenues albidas plurimas gerentibus stipata ; seminibus 
obovato-subglobosis compressis rugoso-tuberculatis opacis. (Plate V. figs. 4-7.) 
ar. B.? CHRYSOCENTRUS: cylindricus, parce e basi ramosus, 10-12-costatus, areolis magnis ; aculeis radialibus 
12-14 albis superioribus setaceis brevibus, inferioribus longioribus robustioribus angulatis compressis rectis s. paulo 
incurvis, centralibus 4, superioribus rigidis robustis basi bulbosis angulatis rectiusculis elongatis, erectis vitellinis, 
inferiore angulato compresso albo recto paulo breviore deflexo ; floribus ex inferiore plante parte ; bacca ovata pulvillis 
paucis aculeos setosos longiores albos gerentibus stipata. (Plate V. figs. 8-10 
On the Cactus mountains and at the head of Williams’s River; degrees 113} longitude. Heads 4-9 inches high, 
single or few, not more than 4-6 together; areola 2-4 lines atatit: Radial spines 3-5 lines long ; upper central 
spines 3 or sometimes 4, black on the upper and horn-colored on the lower side and towards the point, 1-1} inches 
long; lower central white, 1}-2 inches long. Position of fruit on lower half of plant much like that of C. chloranthus, 
Engelm. ined., only 6-8 lish long, crowned with the remains of the (red ?) flower. Seed 0.6-0.7 line long, com- 
pressed ; tubercles sometimes irregularly confluent, and leaving pits between the ridges ; lower part of the back with 
a smooth carina ; hilum oval. 
Var. 8. CHRYSOCENTRUS —named after its deep golden-yellow spines —is probably not specifically distinct, 
though the straighter, stouter, and less divergent spines give it a very peculiar appearance. It was found where 
C. variegatus disappears on the lower part of Williams’s River, and was seen from there to the Mojave Creek, and up 
that stream to the Sierra Nevada. Stems 5-10 inches high; areole 6-7 lines distant, young ones 2}~-3 lines in 
diameter. Upper radial spines 3-5, lateral 5-7, and lower ones 7-12 lines long, the latter flattened and 
often curved up; upper central spines 3 or sometimes 4, 2-3 inches long, bulbous and angular at base, terete [36] 
above; lower central spine 14-2} inches long, flattened. Spines on fruit 3-8 lines long, fewer and stouter than 
in the other form. 
Cereus Engelmanni, Parry, has been found abundantly by Mr. A. Schott on the lower Gila. A specimen 
brought home evidently seems to unite them, and consequently C. variegutus and C. chrysocentrus are to be considered 
forms of it. 
am acquainted with the habitus of about fifteen or sixteen species of the subgenus Ecurnocerevs. All of them 
are of low growth (I write of those only with which I am acquainted), never more than 12, seldom more than 8, and 
often less than 5 inches in height. All also are more or less cespitose, or branching from the root; some of them 
slightly, others i much so, Cereus viridiflorus, chloranthus, sos ESE ctenoides, cespitosus, longisetus, Fendleri, 
gonacanthus, rus, paucispinus, and Engelmanni grow in small irregular tufts or masses, some of the joints or 
stems being much taller than others. Some of them, such as C. viridiflorus, dasyacanthus, ctenoides, ceespitosus, and 
are often nearly simple, or res but few branches ; while others, such as C. chloranthus, longisetus, 
aaa hexeedrus, paucispinus, and Engelmanni, have usually 8-20 joints. 0. polyacanthus, phaniceus, and 
enneacanthus are much branched, and grow in somewhat flattened masses, sometimes with a circular outline, but not 
always, all the joints being of nearly an equal height. €. stramineus always forms a dense hemispherical mass, of a 
perfectly regular contour, — the central joints being the oldest and longest, — 9-12 inches high, gradually subsiding 
towards the circumference of the mass until the extreme outer stems are not more than 2 inches high. C. Maja- 
vensis often grows similarly, but I have also seen it in much broader masses, containing 500-800 heads or joints ; in 
such cases it is always flattened on the top. Where this state occurs, the central joints are as high as in the hemi- 
spherical masses, but the mae eyed contour is destroyed by the longitudinal extension of the joints, forming masses 
sometimes 4 or 5 feet in diameter. C. pharniceus and C. conoideus — two forms which Dr. Engelmann has united into 
sub-species — are quite different in their manner of growth. C. pheniceus, as stated above, grows in irregular flattened 
masses, while C. concideus has the more élevated and somewhat hemispherical shape of C. stramineus. On account of 
