TOR REIP PS NF ET ne SE T. S re Gere a AO ee mere ogre 
289 
ON MAMMILLARIA SCHEERII, Mühlenpf., A RARE 
z MEXICAN CACTUS. 
By BERTHOLD Seemann, Pu.D., F.LS. 
(PraATE X.) 
À few years ago Prinee Salm-Dyck gave me for publication the 
drawing of a rare Mammillaria which had been named in honour of 
his friend Mr. Frederick Scheer, of Northfleet. The Mammillaria had 
flowered in the Prince’s gardens, and as it has long since disappeared 
from our horticultural establishments, I now fulfil the request of the 
eminent botanist, too long deferred, in giving a coloured plate of this 
Cactus. 
Mammillaria Scheerii was received in 1845 from Chihuahua, one of 
the northern states of Mexico, where it had been discovered with many 
other singular and beautiful Cactee by John Potts, Esq., the proprietor 
of the Mint of that state. In 1847, Dr. Mühlenpfordt, of Hanover, 
gave in the Berlin * Gartenzeitung’ a description and a plate of it; but 
the specimen figured was not in flower, so that our Plate is the first re- 
Presentation of the perfect plant. 
Our Mammillaria was also met with in Emory’s Mexican Boundary 
Survey, and is enumerated in Dr. Engelmann’s valuable work on the 
Cactee collected during that expedition, where also a variety B (?) 
. valida is mentioned. A few additional particulars about the plant 
are given by Mr. Scheer in my ‘ Botany of the Voyage of H.M.S. 
erald,” where also the loss of the plant in our gardens is announced. 
The Mammillaria belongs to the section Aulacothele, Salm-Dyck, and 
Dr. Engelmann’s subgenus Coryphantha, and is closely allied to M. 
Salm-Dyckiana, Scheer. Dr. Engelmann calls it a stately plant, by 
far the largest of northern Mammillarie, and continues :—“ Largest 
Specimens before me are 7 inches high and 5 inches in diameter with- 
out the spines.” The plant represented in our plate is therefore not 
fully developed in size. Indeed, I have seen garden specimens nearly 
coming up to the measurement given by the last-named author—one 
of the few who has not deserted the study of Cactee when that singu- 
lar tribe of plants ceased to be fashionable. 
MAMMILLARIA Scheerii ; robusta, magnimamma, globosa, ad basin 
Prolifera, arillis latis tomentosis, mammillis glaucescentibus remotis 
VOL, 1. 
