PAPERS ON BOTANY 121 



Opuntm shreveana. sp. nov. 



Type loc : Tucson, Arizona. 



Distribution: Tucson, south and westeward. 



Plant 60 to 140 cm. high, nearly as broad as tall with a 

 short and somewhat definite trunk. Joints circular or 

 broader than long. 2dm. or more. Blue gi'een, with a 

 space about the areoles and the margins deep purple or 

 sometimes especially in new growth pinkish or purplish 

 throughout. Areoles 1.5 cm. apart bearing chestnut brown 

 bristles, usually spineless, when present usually 1 or 2, 

 needle-like and chestnut brown, 2 to 4 mm. long. Flowers 

 deep yellow, 6 to 7 cm. across. Fruit purplish, short oblong 

 with shallow umbellicus. One of our handsomest plat 

 optunia material and data furnished by Forrest Shreve, 

 Desert laboratory, Tucson, Arizona. 



Two specimens also in ITackensen's collection without 

 data or number, one from Haines Wells, Arizona. While 

 other genera of the family have also been considered, the 

 Opt una on account of their more diversified characters and 

 more abundant distribution has furnished the best field 

 and in addition, the following notations may be useful to 

 future botanists who undertake their study. 



It was my original idea to adjust the descriptions to the 

 more definite types of already well defined species so as to 

 coyer the frequent large quantity of near related and not 

 sufiftciently distinct types, so that the great maze of yaria- 

 tions can be definitely referred to some recognized type, 

 and to exact a type locality where typical specimens of 

 each species and variety accredited to the United States 

 can be secured. 



The portion east of the Missippi except part of the lower 

 regions of Florida has been fairly well canvassed and 

 examined and the following species can be reported: 

 Opiiutia opiintia occurs intermittently along the Atlantic 

 coast from Rhode Island south at least to Titusville, Fla., 

 eastward in Florida and very abundant in Polk County. 

 0. austrina (not true to description, veiy much resembling 

 0. tennispina^ but always smaller and sub-prostrate) Palm 

 Beach to Miami and inland. 



