22 CACTACEOUS PLANTS. 



M. Odieriana, Lemaire. — Ad attractive plant, especially when in flower, 

 but at ail times it is one of the neatest of the genus, its spines being very 

 regularly arranged, and the contrast in colour between the inner and outer 

 series is striking. Stem cylindrical, 3 to 4 inches high, 2 inches in diameter, 

 Tery symmetrical ; tubercles one-eighth of an inch long, dark green ; spines 

 in two series, the outer close and fine, the inner tawny, half an inch to three- 

 quarters of an inch long. Flowers reddish violet. 



M. PAPatiNSONii, Ehrenherg. — A very distinct species, of bold habit, and 

 attaining a larger size under culture than the majority of the Mamillarias. 

 It is found in several districts of Mexico, principally on calcareous rocks. 

 It has been cultivated in England and on the Continent for some years, but 

 the date of its introduction is uncertain. Stout-growing ; stem 4 to 8 inches 

 high, 2 to 3 inches in diameter ; tubercles small, each bearing a star of 

 diminutive white hairs, and four to five stifE erect white spines 1 to IJ inch 

 long tipped with brown ; flowers yellow. When grown as it is in the 

 Oxford Botanic Garden this is one of the most beautiful of all the species, 

 the spines being pure white and very numerous. 



M. PECTINATA, Engelmann. — Few of the Mamillarias equal this in beauty, 

 and it is much to be regretted that the plant continues so scarce in English 

 collections. It is an example of Dr. Engelmann's sub-genus Coryphanta, and 

 is said to be found on the limestone hills of the Pecos, whence it was intro- 

 duced to Europe about twenty or thirty years since. The flowers last a 

 very short time, generally only about two hours in the middle of the day, 

 but they are succeeded by fruits half an inch long, which remain attached to 

 the plant for a considerable time. Stem conical or nearly globular, about 

 3 inches high and 2i inches in diameter; tubercles short and stout, each 

 crowned with a rosette of white spines on one series, very even in size and 

 regularly spreading half an inch or more across each star. Flowers yellow, 

 generally produced singly from the apex of the plant and comparatively 

 large, 2 inches in diameter, with very narrow and numerous petals, the 

 sepals being also numerous, the outer reddish green and the inner resembling 

 the petals. The woodcut (fig. 3) is an accurate reproduction of Engel- 

 mann's admirable engraving in the " Cactacese of the Boundary." 



M. PHTMATOTHELE, Bergm. — A strong-growing plant, which has been in 

 cultivation in Europe for forty years or more, and is now found in most 

 English collections. Its name signifies " tumour-nipple," and refers to the 

 swollen tubercles. Several species of Mamillaria have the specific names 

 terminating with " thele," bearing the same signification with a qualifying 

 prefix, as microthele, small nipple ; macrothele, large nipple ; and polythele, 

 many nipples. In others the Latin is substituted for the Greek, and we have 

 longimamma and magnimamma with corresponding meanings. Stem 5 to 

 6 inches high, 2 inches in diameter ; tubercles a quarter of an inch long,, 

 conical, dark green, crowned with a small tuft of white down, a few white, 

 spreading, hair-like spines, and four to six erect yellowish-red central spines 

 about half an inch long. Flowers bright rose. 



