216 BOTANICAL GAZETTE. | August, 
caries are very fond of its roots. On the sandy plains below the 
cafion we find Dalea pogonathera, Cevallia sinuata, Menodora 
longiflora, Leucophyllum Texanum, Mimosa Berlandieri, and 
Lindheimeri; in the richest part of the prairie, Eupatorium 
Greggii and Desmanthus reticulatus. 
gnats, mosquitoes, and other insects, but the dry weather had now 
set in, the heat was increasing alarmingly, the water was sinking 
disappear. Our team was jaded, our provisions consumed, our 
clothes in tatters, our finances exhausted. We had either to refit 
our expedition or retreat, hence after consultation, the march on 
Mexico was postponed and a retreat ordered. 
valde was the most south-western point visited by our expe- 
dition, where we found Malvastrum tricuspidatum. Along the 
Frio, nearly dry all the way, were found Aristolochia longifolia 
and Oxalis dichondreefolia, and two fine shrubs, Anisacanthus 
Wrightii, Sanvitalia ocymoides, Helianthus ciliaris, and Jatro- 
pha Berlandieri. On the banks of the Seco we gathered Marsilia 
macropoda, Neptunia pubescens, and Synedrella vialis.’ We no- 
ticed also, climbing on the mesquit, the singular Ephedra pedun- 
eulata, but with neither flower nor fruit. 
_ For the most part the vegetation along the return route was 
similar to that we had met earlier in coming out, and towards the 
of July we reached home. 
