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Mexicairiplateau. This enormous ,cactus littained generally a height of l'j 
% feet; specimens 3 feet hig^ were rare, butf one specimen was found 
!|vhich measured 4 feet in height/and near 7 feet in circumference; its top , 
*Was covered with buds, flovyers, and fruits, in all stages of development. 
In size it ranges next to Echinocactus ingens , Zncc., speciSnens of which 
5 to 6 feet high were Collected near Zimapan, in Mexico. Another Mexi¬ 
cali cactus, E.platyceras, Lem., is said to grow 6, and even 10 feet high, 
and proportionately thick. E. Wislizeni is therefore the third in size in* 
• thijs genus. 
^ From the same neighborhood ^a beautiful Mammillaria was sent in 
dried, as well as living specimens! It appears to be one of the few Mam- 
millariae i longimammae , though it differs in having purple, not yellow 
Bowers/and stiffer spines. By the name I f have given it, M. macrome - 
m/ s 1 intended to indicate the unusually large size of different parts of 
the plartt, the tubercles, the spine^ and the flowers. 
" In the same region a strange plant whs obtained" for the first time, but 
then without flowers or fruit, and which, to the casual observer, appealed 
/as curious as it is puzzling to the scientific botanist; single spiny sticks or 
stems having a loft and brittle wood, and a great deal of pith in .the centre, 
* one or more frpm thb same roui/uut always without branches, 8 to 10 feet 
ihigh, not more than half an irtch thick, frequently overtopping the brush 
/among which they were found, only towards the top with a few bunches 
of f already yello^v fleaves. In the following spring the splendid crimson 
flowers of this plant were found by Dr* W. between Chihtfahua and Par- 
iias, an d to Dr . Gregg I am indebted for mature fruit, collected near 
tillo^anfl^MSDt^eyT The plantTproved to be a Fouquiera , two species of 
which had been found in Mexico my Hitmboldt; one of them, the F. for - 
%osci, a branching shrub, was only known in the flowering state; the 
bfnpr, F. spinosa, a spinous tree, only in fruit. The structure of^the 
^Rary of "the first appeared to differ so much from that of the capsule of 
tnd second, that it wqs afterwards deemed ndeessary to distinguish both 
Lgenericairy,i^ind the second constituted then the genus Bronnia. Having 
moth flowers and^fruit of | third Fouquiera) I afh enabled to solve the dif- 
yellow flowers 2 to 2\ inches in length, campa^nulate; fruit to 1J- 
inch long, topped with the remnants of the flower of the same length"; 
Seeds black, rough;, obliquely oval,. with considerable albumen, in which 
the ciirvedcotyledons#re partly buried. 
; M 5 Mammillaria macromeris , n. sp. simplex, ovata, tuberculis laxis, 
e bajp latiore elortgatis cylindricis/incufvis, suleatis; areolis^unioribus silbo- 
bjmentosis; aCuleis angulatis. rectis, elongatis, omnibus porrectis; radiali- 
bus^sub-12 tehuioribus, albiflis; centralibus- sub-3 TQbustioribul, Jbngiori- 
bus, fuspisf* floribus maximis, ro$eis; sepalis , ovatiss, acutis, fimbriatis; 
petalis mucronatis, fimbriatis; stylo supra sfemina brevia longe^ exserto, 
stigmatfbus 8. » 
Sandy soil near Donana, in flower in August. All my/specimens sin¬ 
gle; trunk oval, l to 2 inches high; tbbercles m 8 rows, 12 to 15Uine§ 
lonsr, incurved: groove at first tomentose down to the tomentose sunra 
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