112 
[ 26 ] 
lizenus collected the living plant and flowers, and Dr. Gregg the r^pjedi 
fruit. It is distinct from the other Echimcacti found in those* regions { 
the membranaceous very thin sepaloid scales on the tube of the flower.,^, 
and the juicy glabrous fruit, in which respect it resembles my E. setispi-^l p 
nus from Texas; E texensis , Hpfr., has a juicy fruit, covered with woolly^ ^ 
and spiny scales; E. Wislizeni and others have a dry fruit, covered with.,] r 
hard scales. 
Ilie of 
My Opuntia frntescens (Plant. Lindh. 1. c. p. 245) which had been 
lected by Mr. Lindheimer along the Colorado and Guadaloupe rivers, iri nE jq 
T exas, was also found south of Chihuahua by Dr. Wislizenu% and agairj yl] w 
along the route near Parras, and below Monterey. The suggestion rhade^ sp j 
in the Plant. Ljndh., that may be a southern variety of O. fragdis o r?e L 
the Upper Missouri, has proved to be erroneous, as they belong to quiU f |j a{e ^ 
distinct sections of the genus Opuntia; O. frutescms, together with Q n f rotn 
vaginata , (vide note 18,) is one of the Qpuntiae cylindraceae gracilioresr, g n( 
and is apparently nearly related to O. leptocaulis DC., but is easily dls^jw 
tinguished by its strong, white, single spines,, while O. lept. has 3 sffor i} ^ 
blackish bristles. 
:e % 
ored^ 
Belongs 
this part of the route ; Argemone Mexidana, white, yellow, or rosecolorw, q , 
was frequently met with ; Samolus ebracteatm occurred in moist place: r 0 ' 
so far inland, and on such elevations, while before it was only known a s 5 en . 
a litoral plant; Malvaceae^ Oenotherae, Asclepiadacvae , Gilide, Solaneat!/^ 
Jusliciae , shrubby Labiatae, were collected of many different species; W ne . ) ? 
the great characteristic of the country were the shrubs forming the oft# . 
impenetrable thickets, called “ chaparrals.” They are mostly spi^Our^, 11 
_ ^ V- u * '• ~ —^ * irjrifewSj 
before me 4 inches in diameter, 3 inches in height; the large recurve^ a ^ J 
spines, especially the stoutest central one, which is of a bluish horncolo^ ° CCI 
with a brown point, and is curved and bent downward like a large fah 3, '™ a 
cover the whole surface of the plant, and give it "a very pretty appearanc 5 .^ 11 ^ 1 
Lower radiating spines 6 to 10, upper 12 to 15 lines long; upper centr 
spines 12 to 18 lines long, but lower stouter one only 10 to 12 lines r ai3t ’ 
length. Flowers described from the shrivelled specimens found on Qf ros > a ° 
living plant; about 1 inch in length, and probably pale red. I have 
doubt that some fruits collected in the same region (about San Lorenz 
by Dr. Gregg belong to this species; the fleshy oval berry is 10 or . 
lines long, covered with the same auriculate thin scales which we fiL™ a J ai 
on the flowers,* and crowned with the remnants of the flower; see * °^ 0r 
black, much compressed, somewhat rough, albumen considerable, em% ,0Var,c 
curved,-cotyledons short Obtuse. This is a very remarkable P^ndBr ut j; 31 
approaches in shape some mammillariae; the tubercles which form t| 0n ^ r °i 
interrupted ribs are sideways compressed, have a tomentose groove l lnc *' le ^ 
their upper edge, which ends in a regular axillary depressed areola, lil ®? r ul 
that of a true mammUlaria; but the scaly ovary and the curved embr/ 31 ^, 
prove it to be an Echinocactm. The specimen brought here by Dr. r J° n &f 
died soon after it arrived, as many of those collected in April and M. 0 diam 
during the flowering season, though only two months on the road, wly av y yt 
those collected the year before, between August and November, a 
had been packed up for eight or ten months, mostly do very well 
Dr. Gregg’s seeds, however, have germinated well. Ilea to*adpi 
