OF ARTS AND SCIENCES. 



293 



Var. a. NIGRICANS : aculeis brevioribus acute angulatis et nigri- 

 cantibus. 



Var. /3. BRUNNEA : pulvillis remotioribus ; aculeis longioribus obtuse 

 angulatis brunneis sursum albidis. 



Var. y. MAJOR : suborbiculata ; pulvillis remotis ; aculeis breviori- 

 bus paucioribus pallidioribus. 



New Mexico : fl. May. Var. a. is found on the Rio Grande near 

 Santa Fe ; /3. in similar sandy locations near El Paso ; and y. in 

 mountainous regions near Santa Fe. — Joints 4-6, or in y. even 8, 

 inches long; spines mostly 1-2 inches in length. Flower about 2 

 inches in diameter, with a short ovary. Fruit 1^-1| inches long, 

 slender, much contracted at base so as to appear almost stipitate. 



O. MojAVENSis, E. & B. in P. R. R. : prostrata ; articulis grandi- 

 bus suborbiculatis ; pulvillis remotis ; setis fulvis ; aculeis 3-6 validis 

 infra fuscis. 



On the Mojave, west of the Colorado. — The material is too scanty 

 to make out where it belongs ; but perhaps it is only a form of 

 O. phceacantha. 



11. O. Camanchica, E. & B. in P. R. R. : prostrata; articulis 

 adscendentibus majusculis suborbiculatis ; pulvillis remotis plerisque 

 armatis ; setis stramineis fulvisve parcis ; aculeis 1-3 compressis 

 fuscis apice pallidioribus, superioribus elongatis suberectis, cseteris 

 deflexis ; bacca ovata late umbilicata ; seminibus majusculis angu- 

 latis hilo excisis. 



Llano Estacado, on the Upper Canadian River. A large, exten- 

 sively spreading plant ; the joints 6-7 inches long ; spines l^- - 2 or 

 even 3 inches long. Fruit large, juicy. Seeds 2-3 lines in diame- 

 ter, very irregular and deeply notched at the hilum. 



12. O. TORTisPiNA, E. & B. 1. c. : prostrata ; articulis adscendenti- 

 bus majusculis suborbiculatis ; pulvillis subremotis ; setis stramineis 

 seu fulvis ; aculeis 3-5 majoribus angulatis ssepe tortis albidis cum 

 2-4 gracilioribus ; bacca ovata late umbilicata ; seminibus majuscu- 

 lis orbiculatis. 



On the Camanche plains, east of the elevated plateau of the Llano 

 Estacado. — Similar in size and habit to the last species, its western 

 neighbor, with more numerous spines than any other of our Opuntice 

 with juicy fruit. Seeds regular, and only very slightly notched at 

 the hilum. 



