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Transactions Texas Academy of Science. 
Selinocarpus, Acleisanthes, Cucurbita foetidissima, Asclep- 
iadora decumbens; Cooperia, Zephyranthes. 
B. Ecological forms marked by absence of storage or succulent 
tissue : mechanical tissues in excess, very compact and hard ; 
stems and branches dwarfed, rigid and often spine tipped; 
leaves much reduced in size or early falling or permanent and 
leathery and otherwise variously protected ; tender, leafy 
shoots appear after sufficient rainfall during the growing sea- 
son— March to November; roots generally much branched and 
far reaching. 
I. Foliage leaves wanting; young shoots develop sappy cortex 
and assimilation tissue; enlarged woody root axis. (Com- 
pare A. IV.) Ephedra. 
II. Leaves wanting or very ephemeral. 
1. Shoots green (except older trunks) tapering to hard 
pointed thorns. Koeberlinia spinosa. 
2. Stem wandlike, armed with stout thorns and thereby 
furrowed. Fonquiera splendens. 
III. Reduced leaves of various forms and variously protected. 
1. Compound leaves, dissected into many leaflets — 
Acacia berlanderi, constricta, greggii; Prosopis glan- 
dulosa and pubescens; Leucaena retusa and pulveru- 
lenta; Calliandra conferta, Mimosa fragrans, bore- 
alis, biuncifera. 
2. Compound leaves especially reduced as to the number 
of small leaflets. Krameria canescens and ramosis- 
sima. Parkinsonia texana. Dalea formosa and 
frutescens. 
3. Leaves protected by glandular secretion. Covillaea 
tridentata. Flourensia cernua, 
4. Leaves minute, ericoid, appressed. Mortonia scab- 
rella and sempervirens. Micro rhamnus ericoides. 
5. Leaves with protective hairy covering. Leucophyllum 
minus and texana. Crotons. Eurotia lanata. 
6. Leaves simple, small, without notable protective de- 
vices. Condalia obovata and spathulata. Zizyphus 
obtusifolia. , Celtis pallida. 
C. Ecological forms designated as short lived annuals. More or 
less protected by various types of pubescence : Not capable of 
enduring long continued drought and therefore develop only 
after copious rains and mature seed quickly, which then lie in 
the dormant condition until a subsequent rainy season. 
