158 CACTACEX OF WHIPPLE’S EXPEDITION. 
This species is very nearly allied to EZ. Parryi, Engelm. Synops. Cact., of the neighborhood of E] Paso; but this 
latter species is depressed globose, much smaller, simple, with only 13 ribs, whiter, less flattened spines. Fruit and 
are said to be the same, but unfortunately have been lost, and cannot be compared. No doubt, satisfactory 
diagnostic characters will be discovered in the seeds. The fruit of Z. horizonthalonius and E. Texensis is also similar; 
the latter, however, though woolly, is not dry. 
Very different in flower and fruit, but very similar in shape, in the many heads, numerous ribs, and stout curved 
annulated spines, is E. cylindraceus, discovered by Dr. Parry a few degrees farther south, on the eastern slope of the 
Sierra. We shall repeatedly have occasion, especially among the Opuntie, to indicate the remarkable analogies in the 
external form or in the more essential character of Cactacea, in different geographical divisions of the southwest. 
CEREUS, Haw. 
Subgen. EcHINOCEREUS. 
1. CEREUS vrrIDIFLoRvs, Engelm. in Wisliz. Rep., sub nom, Echinocereus. 
On the plains east of New Mexico, near the 100th degree of longitude, to the mountains of the Rio Grande, 
Sept. 12, 1853. 
2. C. cxsprtosus, Engelm. in Plant. Lindh. 1. c. The most eastern of all our Cerei ! and only found in the 
plains. It was first seen about 170 miles west of Fort Smith, near the 96th degree, about the same longitude where 
Mr. Lindheimer first discovered it on the Brazos, four degrees farther south. Its western limit seems to be near the 
100th degree, where the range of C. viridiflorus commences. 
It may not be uninteresting to observe that this is the first time that this interesting genus has been recognized 
within the boundaries of the United States under the acquisition of Louisiana. 
3. OC. Fenptert, Engelm. in Plant. Fendl. Seen first on the high plains 50 miles east of the Pecos, about [33] 
the 105th degree, and extending from there over the mountains of New Mexico westward to the Aztec moun- 
tains, near the 113th degree. Southward it has been seen as far as El Paso. 
The ovate or mostly elongated cylindric heads are simple or few together, and of a dark green color. They 
are characterized by the dark central spine, which is very bulbous and curved upwards, and by the lower radial spines 
being by far the stoutest, the lowest being 4-angular. Flower and fruit have been described elsewhere. 
Var. 8. PAUPERCULUS, with only about 6 spines, the central one assuming the place of an upper radial spine, was 
also found near the Pecos. It hardly deserves the designation of a distinct variety, as occasionally complete bunches 
of spines occur on the same plants with the depauperate ones, 
4. C. MosAVENSIS, sp. nov.: ovatus, dense ceespitosus, 10-11-costatus, glaucescens; areolis orbiculatis junioribus 
dense albo-tomentosis distantibus ; aculeis basi bulbosis teretiusculis s. subangulatis robustis elongatis curvatis, 
radialibus 7-8, infimo superioribusque debilioribus, lateralibus longioribus, centrali singulo angulato sursum incurvato. 
(Plate IV. fig. 8.) 
Var. B.? ZUNIENSIS: dense cexspitosis 10-costatus, areolis paulo minoribus, aculeis tenuioribus basi bulbosis 
quadrangulatis rectis s. paulo curvatis flexuosisve, radialibus 8 infimo graciliore, sammo robustiore longivreque, centrali 
singulo robustiore longiore recto s. sursum incurvo. (Plate IV. fig. 9.) 
Found between the Rio Colorado and Mojave Creek, with Echinocactus polycephalus and Opuntia erinacea, etc., 
a region rich in rare Cactacee. The oval heads, 2-3 inches high and 14-2 inches in diameter, form dense cespitose 
masses much like C. phaniceus. The areole are 3 lines in diameter, 6 lines or more distant from one another. The 
long and very bulbous spines are curved and interlocked so as almost to hide the body of the plant. Upper and 
lower radial spines 9-15 lines, the uppermost one wanting or weaker than the rest; lateral spines 15-25 lines long, 
ashy-red when young; central spine more angled, 14-2} inches long, dusky ; all spines ashy-gray when old. 
C. Zuniensis seems to form an intermediate link between this and the next species, but resembles most the 
former, to which for the present, not knowing flower and fruit, we doubtfully draw it asa variety, It was found 
near Caiion Diablo, on the Colorado Chiquito, about 120 miles west of Zufii. Its manner of growth and whole 
appearance is very much like that of the Mojave species. The spines are weaker, straighter, and more angular; the 
principal difference consists in the stout upper radial spine, which is similar to the central spine, Young areole 
nearly 3 lines in diameter, 4-6 lines distant. Lowest radial spine 6-9 lines, lateral ones 9-15, and upper 
one 12-18 lines long; central spine 14-2 inches long, very bulbous at base. Young spines straw-colored, old 
ones ashy. 
C.. Mojavensis seems to be nearly allied to C. Fendleri (in both the spines are very bulbous at base, the central 
one single, angular, and curved upwards), but the cespitose growth, glaucous color, longer radial spines, — the lowest 
one of which is weakest, — seem to distinguish it. The examination of numerous specimens ‘n loco, and the flower and 
fruit, only can decide here whether they are distinct, or forms of a single species ; and this, indeed, is the case with all 
