CACTACE^ OF MEXICO — SAFFOED. 531 



thalonhis^ E. longihcmiatus^ and E. lopothele. Very closely allied to 

 the last is a form collected by Mathsson, in the Rinconado Pass, be- 

 tween Saltillo and Monterey, named Echinocactus rinconadensis. 



On our return trip we collected the glass-needled alicoche {Echino- 

 cereus conglomeratus) ^ and the pretty little button-cactus Mamillaria 

 greggii (pi. 4, fig. 1), a species very closely allied to M. micromeris of 

 Texas. Like many of its congeners it bears little crimson club- 

 shaped chilitos, which are relished for their pleasant acidulous, cran- 

 berry-like flavor. When we reached the hacienda Don Jose Maria 

 insisted on adding to my collection some of the rarest species of his 

 garden. I offered to pay for them, for I knew that he sometimes 

 sold plants to dealers, but he declined with polite dignity to receive 

 money, saying : " No, Senor ; that would spoil all my pleasure. If 

 I might ask a favor, however, I beg that you send me a few books 

 which treat of Cactacese, books with pictures, for I can not read 

 English nor German, and I have only this catalogue to guide me. 

 I have some idea of the various groups of plants, but it is sometimes 

 hard to distinguish a Mamillaria from an Echinocactus, though I 

 know that in general the Mamillarias bear chilitos, and the Echino- 

 cacti have scaly fruits. I know of no book in Spanish to help a 

 cactus lover, though this is the country of the Cactacese. Ah, Seilor, 

 what a great help illustrations are ! " 



I accepted Don Jose Maria's plants with thanks, and told him 

 that I would try to prepare a guide to the study of Mexican Cactacese, 

 such as might help an amateur collector, explaining by figures, as 

 well as possible, the differences between the genera, describing the 

 flowers, the structure of the plants, and the uses to which many of 

 them are applied. 



It will not be possible within the limits of the present paper to 

 enumerate all the plants collected and observed during my recent 

 Mexican journey. In the vicinity of Saltillo I collected many of 

 the same species as in Nuevo Leon, including the strange-looking 

 Echinocactus capricornus, with tufts of twisted spines and beau- 

 tiful flowers (pi. 5, fig. 2), Lophophora wilUamsii, Mmnillai'ia leona^ 

 M. conoidea^ Echinocereus conglomeratiis, and the species resembling 

 E. stramineus. In addition to these was a species of Ariocarpus 

 (^1. furfuraceus)^ locally known as " chautle," which is quite distinct 

 from A. retusus (also known as A. prismaticus) , a species I saw 

 in the Monterey collection, though the two species are held by some 

 authorities to be identical.* 



In the vicinity of Parras, Coahuila, in addition to many of the same 

 species as those I had already collected, I found a species of Ariocar- 

 pus (pi. 5, fig. 1) very closely resembling the well-known " living 



° Scliumanu. Karl. Op. cit., pp. 005-G06. 



