cactus

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cactus

A regionally popular short form for
(1) Peyote, or
(2) Mescaline.

cactus

the common name for members of the family Cactaceae, all of which, with one possible exception (Rhipsalis), are native to the continent of America. Most cacti are XEROPHYTES and succulents, found in deserts which have infrequent but heavy rainfall; cacti are absent from deserts with little or no rainfall. Epiphylum species and their relatives are found in rain forests and are chiefly EPIPHYTES. Cacti are distinguished from other succulents by having an areole, a pin-cushion type of structure from which wool, spines, new shoots and flowers develop. Other succulents do not possess an areole even though spines may be present.
References in periodicals archive ?
Mauseth and Plemons have hypothesized that seven lines of evolution exist for Cactoideae wood.
Characterization of secondary phloem in members of Cactoideae is scarce (Mauseth & Ross, 1988: Loza.
In all of the Cactoideae that we studied, the periderm originates from epidermal cells and develops late in most species, beginning as patches at the base of the stem (Mauseth & Ross, 1988; Mauseth et al.
One of the interesting results of these phylogenetic analyses based on structural characters is our finding that the subfamily Cactoideae is a supported clade (b74/j66% and b60/j55%), recovered as monophyletic in both analyses, based on the presence of highly reduced leaves (character 8), interpreted as the synapomorphy for the clade.
The other morphological characters mentioned by Anderson-the presence of caepitose, unsegmented globose stems (5), of an undifferentiated fertile zone (15), flowers open during the day (29), and a naked pericarpel (25)-have also appeared independently in other Cactoideae taxa.
All of these features evolved independently in other taxa of Cactoideae.
This genus is recovered as basal to the whole Cactoideae (Fig.