296 PROCEEDINGS Or THE AMERICAN ACADEMY 



ssepe 2-3 minoribus ; stigmatibus 8 ; bacca obovata ; seminibus un- 

 dulato-marginatis majusculis. 



Var. ^. MONTANA : subinermis ; stramineo-setosa. 



Along the Canadian River east of the Llano Estacado, and on that 

 plain. Vav. ^3. near Albuquerque. — Joints 2^-- 3 inches in diameter, 

 in /3. larger; longer spines 1-2 inches long. Fruit short, pulpy, 

 sweet. Seed 2^ lines in diameter, with a very sharp irregularly wavy 

 or twisted border. — The var, /3. seems to unite the common 0. Raji' 

 nesquii with this form. '^ 



O. sTENOCHiLA, E. & B. 1. c. : prostrata ; articulis obovatis ; pulvil- 

 lis remotis stramineo-setosis, superioribus solum armatis ; aculeis sin- 

 gulis albidis patulis, 1-2 minoribus deflexis ssepe adjecti% ; bacca obo- 

 vata clavata ; seminibus crassis anguste marginatis. 



Zuni, Western New Mexico. — Joints 4 inches long and 3 wide ; 

 spines 1-1:|- inches long. Fruit green or pale red, very juicy, 14 or 

 sometimes even 2^ inches long. Seeds quite peculiar, i-egular, much 

 thicker in proportion than those of most other Opuntics, and with a 

 very narrow edge. — Another form, with smaller and rounder joints, 

 more spines, smaller fruit, but similar seeds, was found in the same 

 neighborhood. 



All the forms described above have fibrous roots. The following 

 are principally characterized by their bulbous or tuberous roots, but 

 can hardly be otherwise distinguished from the forms already de- 

 scribed. Both are found westward of the range of 0. Rafinesquii 

 proper, and may be considered as subspecies, the peculiarities of 

 which are readily propagated by seeds. 



O. MACRORHizA, E. in PI. Lindh. part 1 : prostrata, ssepe adscen- 

 dens, radicibus tuberosis ; articulis obovato-orbiculatis perviridibus ; 

 pulvillis subremotis rufo-setosis, superioribus solum armatis; aculeis 

 singulis validis ssepe variegatis patulis, 1-2 gracilioribus deflexis sub- 

 inde additis ; alabastro acuminato ; petalis circiter 8 sulphureis basi 

 miniatis ; stigmatibus 5 ; bacca obovata basi clavata, umbilico lato ; 

 seminibus subregularibus compressis minoribus. 



Sterile, rocky places on the Upper Guadalupe River, in Texas : fl. 

 May and June. — Roots in young specimens fusiform, in old ones 

 enlarged to fleshy tubers, sometimes 2 or 3 inches in diameter. 

 Joints 2J - 31 inches long, the leaves and bristles the same as in O. 

 Rafinesquii. Flowers 3 inches in diameter. Fruit green or pale 

 purple, smaller and sweeter than that of 0. Rafinesquii. 



