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 ?
Cactoideae seeds show considerable variation in their shape, size, structure and testa color (Barthlott and Hunt, 2000).
The number of seeds per fruit may also depend on the age and size of the plant, the number of flowers produced, and the origin (wild or cultivated species), as demonstrated for Cactoideae (Parker, 1987; Leon de la Luz and Dominguez-Cadena, 1991; Rojas-Arechiga et al.
Further work on the mechanisms of germination is needed, particularly on the requirements for the germination of seeds of other Cactoideae, with the aim of contributing to their use, management and conservation.
Barthlott W, Hunt D (2000) Seed Diversity in the Subfamily Cactoideae.
Terrazas T, Arias S (2003) Comparative stem anatomy in the subfamily Cactoideae.
Loza-Cornejo S, Terrazas T (2003) Epidermal and hypodermal characteristics in North American Cactoideae (Cactaceae).
Berger (1929) recognized Schumann's subfamilies and the 41 genera in Cactoideae that were grouped in two tribes, Cereeae and Rhipsalideae.
Basic anatomical features of Cactoideae have been studied since the sixteenth century, focusing on selected features related to the different external forms or to stem photosynthesis.
He observed that leaves are vestigial in all of the Cactoideae species he studied.
Anatomical characters are rarely incorporated into phylogenetic analyses of Cactoideae.
For this analysis, 41 genera of Cactoideae were selected to represent the nine tribes proposed by Barthlott and Hunt (1993); two genera of Opuntioideae were also selected.
Dermal features appear to be the most informative stem characters in several groups of Cactoideae.