84 Standley : Some Echinocerei of New Mexico 



a discussion of the synonymy of the group and a list of a few of 

 the herbarium specimens examined. 



Of all the characters that have been discussed here there is no 

 single one that can be depended upon absolutely for the separation 

 of species. Those of the spines, especially the centrals, are proba- 

 bly.of more value than any others. For the separation of the four 

 species I would offer the following key based upon the spines : 



Centrals mostly six ; flowers small ; petals almost acute. E. neo-mexicanus. 



Centrals three to five, mostly four ; flowers larger ; petals broadly 



obtuse. 

 Centrals slender, white or straw-color, 14-40 mm. long, plant 



depressed at top. E. coccineus. 



Centrals stout, terete, usually gray or dark-gray, 15-50 mm. 



long, plant usually obtuse. E> polyacantkus. 



Centrals slender, more or less angled, somewhat curved, usually 



ashy-gray, 25-80 mm. long, plant rather acute or conical at 



the top. E.conoidtm. 



Echinocereus coccineus Engelm. Wisliz. Rep. 9. 184 8 

 Cereus coccineus Engelm. PI. Fendl. 50. 1849. 



Mt 



may 



phoeniceus Engelm. Synop. Cact. 284. 1856. 



aggregates Coult. Cont. Nat. Herb. 3: 396. 1896. 



unmillaria aggregate Engelm. Emory's Rep. 1 5 5- l8 4 » 



; the same species. There is, however, no type specimen 

 existing of this species, and although the original description is 

 accompanied by a drawing of the plant, this drawing is of such a 

 general nature and the description is so brief that it is impossib e 

 to tell to just what it refers. The plant illustrated might be either 

 of the species discussed here. In this difficult group of plants it 

 is well to accept only those species of whose identity we are 

 reasonably certain. Consequently it is better to neglect this name 

 for one of which we still have the type specimen. 



Specimens examined : 



Wish 



New Mexico: banta re, 1840, Wi ,. 



Fendler 272 ; Burro Mountains, Grant County, May 20, I9°3- 

 B. Metcalfe 82 (the sheets that I have seen, at least); Uppe r 

 Pecos, Oct. 13, 1853, J. M. Bigefow; Anton Chico, 1853, Bl ^' 

 loiv ; also numerous specimens in the cactus garden of the Ag r 



1 <-» n _-ii._ t „j „., «.i „„ ,., a ^ ^r *i,*» r>rcran Moun- 



