MAMILLARIA. 89 



whitish, with black tips. Flowers in May, yellowish-white, with 

 streaks of red. Mexico. Should be grown in a frame in summer, 

 and wintered on a shelf in a greenhouse. The variety iexana differs 

 in being more densely clothed with spines. It will form tufts 

 1 foot in diameter. (Fig. 45.) 



M. pycnacantha. 



Stem 6 inches high, tubercles rather large, swollen, with 

 tufts of short white wool in their axils, and stellate clusters 

 of spines springing from disks of white wool on the top ; 

 spines ?> inch long, flattened, pale brown. Flowers large, produced 

 in July in clusters on the top of the stem, about half-a-dozen 

 opening together ; colour a deep sulphur yellow, anthers orange. 

 Mexico. Introduced 1840. This is a beautiful little plant, which 

 should be grown in a warm greenhouse all the year round. Old 

 stems develop offsets from tl/e base, by which the species may be 

 multiplied. 



Fig. 46. Mamillaria sanguinea. 



M. sanguinea. 



Stem 6 inches high, and 4 inches through ; tubercles crowded, 

 short, bearing stellate tufts of shortish spines, and projecting 

 longer ones, all being bristly and yellow. Flowers produced in 

 June in a circle on the top of the stem, a strong plant having about 

 forty flowers open together. Each | inch long and wide, and coloured 

 bright crimson, with yellow anthers. Mexico. The plant figured 

 is a young one, showing the spines much longer than is usual on 

 mature specimens. (Fig. 46.) 



