[26] 92 
amined by me; and E£chinocactus, mostly with a curved embryo. The 
- second class includes Eechinocereus, with a nearly straight embryo, and 
the direction of the cotyledons,) or C. apici florae, (from the position of the 
flowe e second class can be named, i 
Cactaceae contrariae, or C. lateriflorae. 
Echinocereus is principally distinguished from Cereus proper by its low 
ted States, where the cactus family is represented only by some Opuntiae 
and Mammillariae. The southern limits of chanocerei are un- 
known to me, but I doubt whether they extend far in that direction ; the 
nearly-related Echinopses, on the contrary, appear to be exclusively inhab- 
i outh America, especially the La Plata countries. 
n Texas. Only two species of true Ceret were seen; one of 
a peculiar type about Chihuahua, and another near the mouth of the Rio 
Grande, which does not appear to differ from the wide-spread C. variabilis, - 
Pfeiff. tiae. ellipticae, as well as cylindraceae, were observed from 
New Mexico to Matamoros, and species of both are also found in Texas. 
lelocacti, locacti, and other genera of Cactaceae, not mentioned 
above, were not met with 
viz: that most species of this family have a very limited geographical 
range, the most striking exception being those belonging to the genus 
