44 UNITED STATES AND MEXICAN BOUNDARY. 
the rind, and, drying up from the heat of the sun, falls to the ground. The innumerable black 
seeds are 0.7-0.9 line long. Those brought by Mr. Thurber, and largely distributed in this 
country and in Europe, have well germinated; the cotyledons are short and acute; the seedling 
plant is globose, grows very slowly, and is rather delicate. 
23. C. Thursert, HE. in Sillim. Journ. : caulibus erectis seu adscentibus elatioribus fasciculatis 
_ articulatis 13-14-costatis ; sinubus planiusculis; areolis subremotis pulvinatis griseo- seu 
fulvo-tomentosis; aculeis 7-15 gracilibus rectis flexuosisve fusco-atris demum cinereis valde 
ineequalibus irregulariter fasciculatis ; floribus infra caulis apicem lateralibus aggregatis ; 
ovarii squamis sepaloideis 80-100 pluribusve triangularibus imbricatis axilla lanam copiosam 
albidam sel fulvam sepeque aculeolos paucos nigricantes gerentibus; sepalis tubi sub-50 
olivaceis, inferioribus acutiusculis, superioribus obovato-spathulatis obtusis; petalis obtusis 
carnosis albidis ; bacca magna globosa aculeolata demum nuda olivacea intus coccinea ; semini- 
bus numerosissimis oblique obvatis dorso carinatis leviusculis (sub lente minutissime tuber- 
culatis) lucidis exalbuminosis; hilo oblongo subbasilari, embryone cotyledonibus foliaceis 
curvatis incumbentibus breviter hamate. (Tab. LX XIV, fig. 15.) 
In a rocky caiion near the mountain pass of Bacuachi, Sonora, Thurber ; on all the sierras of 
Sonora westward of the Sierra Madre, and more common southward, Schott ; called there Pita- 
haya: fl. June and July ; fruit in July and August.—Stems 5~15 from one root, fasciculated, 
erect or ascending, ‘‘ curved inward,’’ 10-15 feet high, articulated, lower joints 2-3, upper 
ones 5-6 feet long, 4-6 inches in diameter; ribs 13~14, very slightly prominent. Theskeleton of 
this species, according to Mr. Schott’s observations, consists of flattened bundles of wood, very 
loosely connected by transverse fibres, so as to form a kind of hollow tube. Areole pulvinate 
covered with brownish or ashy wool, only about three lines in diameter, 12-15 lines apart. 
Spines irregularly fasciculated, 7-10, according to Mr. Scholt’s notes; but 15 in the flower- 
bearing bunches before me. (Might not the flower-bearing spines be more numerous and per- 
haps more slender than the others, indicating a transition to Pilocereus ?) Spines slender, flex- 
ible, almost setaceous. very unegal in length, 5-18 lines long in the same bunch, partly 
deciduous. Flowers usually 6-12 inches below the top of the plant, about 3 inches in length; 
ovary very densely imbricate with sepaloid scales, which bear dirty wool and often short bristly 
spines in their axils ; in some specimens they are wanting, in others they also invest the fruit, 
but are easily brushed off at maturity. Fruit 3 inches in diameter, like a large orange, of deli- 
cious taste, the crimson pulp dotted with numerous black seeds. These are 0.9-1.0 line long 
only, a little larger than those of the last species, which they very much resemble, and very 
minutely tuberculated. The seeds germinate like those of (, giganteus, with very short acute 
cotyledons, and grow up with a globose head like the Echinoceres while all the Eucerei which 
I have seen germinating at once grow up in a cylindric or prismatic column. 
Subgen. 4. Priocersgvs.* 
24. C, Scuormm, (sp. nov.): caulibus suberectis elatioribus fasciculatis articulatis 4—7- 
(plerumque 5-) costatis flavo-viridibus ; areolis in caulibus sterilibus remotis aculeos radiales 
* Cereus Schottii, described in the text (evidently a Pilocereus, as that genus has been established by Lemai 
a : . : a b 
in my mind about the propriety and necessity of a reunion of the “ Old man Cactus” a J Lge Lota 
Pilocereus would be characterized by the difference of the sterile and the flo 
smaller flowers with all the parts reduced in number 
surface of the tube and even from the top of the ovary ,- 
our species, 
The other characters ascribed to Pilocereus (filaments from the whole 
and especially the short and globose cotyledons,) are not found in 
