290 PROCEEDINGS OF THE AMERICAN ACADEMY 



Subgen. 2. Platopuntia, E. 1. c. Articuli complanati : Acres 

 magni : bacca pulposa vel rarius sicca : semina late marginata : em- 

 bryo plusquam circularis circa albumen parcum spiraliter convolutus : 

 cotyledones semper contrarise. 



§ 1. Micro carpece : suberectce : aculei plurimi, colorati : bacca parva 



subglobosa, 



2. O. Strigil, E, in B, C. R. : suberecta, articulis ovatis orbicu- 

 latisve ; pulvillis confertis ; aculeis 5-8 radiantibus deflexis rufis 

 apice flavis ; bacca parva late umbilicata rubra ; seminibus parvis 

 anguste marginatis. 



Between the Pecos and El Paso. — Plant 2 feet high ; joints 4-5 

 inches long ; spines an inch or less in length. Fruit 6-7 lines long. 



§ 2. Grandes : erectae seu procumbentes : articuli magni : aculei 

 pauci, validi, compressi, plerumque colorati : bacca major vel mag- 

 na, plerumque ovata. 



* Suiinermes. 



3. O. Ficus-Indica, Mill : cultivated south of the Rio Grande, un- 

 der the name Nopal Castillano. 



*■ * Flavispince. 

 f Erectce. 



4. O. Tuna, Mill : cultivated about the old missions in the southern 

 parts of Upper California, under the name Tuna. Specimens gath- 

 ered at Beaufort, on the coast of South Carolina, (probably introduced,) 

 may belong here. 



5. O. Engelmanni, Salm : erecta, grandis ; articulis obovatis ; pul- 

 villis remotis setas stramineas rigidas insequales aculeosque 1-3 com- 

 presses stramineos basi rufos gerentibus ; floris flavi intus rubelli ova- 

 rio subgloboso ; stigmatibus 8 - 10 ; bacca obovata late umbilicata ; 

 seminibus minoribus. 



From the Canadian River to the mouth of the Rio Grande, and 

 westward from the Gulf to Chihuahua and El Paso : fl. May and 

 June. — Plant 4-6 feet high ; joints a foot long or less ; leaves subu- 

 late, 3-4 lines long ; larger spines 1 - 1| inches long. Flower 2^ 

 - 3 inches in diameter. Fruit usually 2 inches long, 1| in diameter, 

 juicy, but of a somewhat nauseous taste. Seeds 1^-2 lines in diam- 

 eter. A plant observed by Dr. Blackie on Bayou Bccuf, Western Lou- 

 isiana, 5| feet high, joints 9 inches long, reddish-yellow flowers, is 

 pi'obably this species. 



