558 



ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 



in their axils. The outer floral leaves are scalelike, the inner elon- 

 gated and sepal-like, and the innermost like true petals. The stamens 

 are numerous and are borne on the tube of the perianth, and the style 

 columnar and bearing a several-rayed stigma. The fruit is usually 

 covered ^yith scales, and often with tufts of minute bristles, in some 

 species surrounded about its base by a thick growth of silkj^ wool. 

 Some of the plants belonging here are composed for the most part 

 of succulent pulp, which is candied and made into preserve like 

 citron. Others possess jDoisonous or narcotic alkaloids, and are used 

 as intoxicants by the Indians. In a few the fruit is edible (pi. 9, 

 fig. 4), and several yield an abundant supply of watery sap, which, 

 though insipid, yields a grateful drink to the 

 thirsty traveler. 



The principal divisions of the Echinocacti, 

 including Mexican species, are the following: 



Cephalocactus, including the great viznagas, 

 Echinocactus 'pahneri (pi. 8) and E. toisUseni, 

 from which sweetmeats are made: E. horison- 

 thalonius (pi. 2, fig. 5), E. hicolor (pi. 13, fig. 2), 

 E. pilosus, and the closely allied crimson-spined 

 E. pringlei (pi. 13, fig. 3). 



Lophophora, represented by the single species 

 Lopliopliora williamsii., the narcotic pej^ote, or 

 mescal button of the Indians (pi. 3, fig. 5). 



Astrophytum, or " starfish cactus," including 

 the spineless " bishop's cap " {Astrophytum 

 Tnyriostigma) ^ A. capricornus (pi. 5, fig. 2), and 

 A. ornatum (pi. 13, fig. 4). 



Euechinocactus, or Echinocactus projoer, in- 

 cluding E. pottsii and E. electr acanthus. 



Ancistrocactus, or hook-spined Echinocactus, 

 divided into two sections, the first composed of species having wiry 

 spines, bent like fishhooks, including Echinocactus longihamatus 

 (pi. 9, fig. 4), the closely allied E. uncinatus^ and E. hrevihamatus 

 (pi. 3, fig. 3) ; the second with dilated horn-like spines, often flat- 

 tened on the upper side, annulated or transversely ribbed and curved 

 near the tip, including Echinocactus cornigerus (pi. 13, fig. 6), £'. 

 texensis (pi. 2, fig. 1)^ E. emoryi°' and E. wislizeni of Arizona. 



Stenocactus, including Echinocactus multicostatus (pi. 4, fig. 3) 

 and its allies (pi. 4, fig. 5), and E. coptonogonus. 



<* For an illustration of an Indian drinking the sap of Echinocactus emoryi, 

 see Coviile, Frederick Vernon " Desert plants as a source of drinking water." 

 Smithsonian Hep. for 1903, pp. 499-505. 1904. 



Fig. 22. — Echinocactus, 

 fruit. 



