Echinocactus. CACTACE^E. 245 



twisted ; the lower are shorter, darker, and terete, and the lowest middle one hooked : 

 flowers 1 to l inches long, yellow : few (2 to 5) rounded fringed sepals on the 

 ovary, 10 to 15 oblong ones on the tube : petals about 8 : stigmas 5 to 7, short : 

 seeds large, minutely tuberculated. Cact. of Pacif. R. Rep. iv. 28, t. 1 ; Bot. Ives 

 Colorado Exp. 12. 



On the lower Colorado, on the confines of California, Arizona, and Utah (Bigelow, Newberry, 

 H. Enfjclmann), and to Southern Colorado, Brandegee. Heads 3 to 5 inches high ; spines 3 to 20 

 or 24 lines long, on prominent tubercles, which give the ribs a wavy or interrupted appearance : 

 seeds 1^ to If lines long. 



2. E. polyancistrus, Engelm. & Big. Heads solitary, middle-sized, ovate to 

 cylindrical, with 1 3 (to 1 7) interrupted ribs : outer spines 20 or more, white, the 

 uppermost broader and longer; central spines 5 to 10, the upper one broadest, long- 

 est, recurved, white, the others brown, terete, and mostly hooked : flowers yellow, 

 2 to 2^ inches long, with about 8 rounded fringed sepals on the ovary : seeds as in 

 the last. Cact. of Pacif. R. Rep. iv. 29, t. 2, fig. 1, 2. 



From the head-waters of the Mohave River (Bigelow) to the sage plains of Southwestern Nevada, 

 Gabb. Perhaps too near the last, from which it is distinguished by the more numerous spines, 

 many of the inner ones being hooked, the larger flowers, and more numerous sepals and petals. 

 Heads 3 to 10 inches high, 2 to 4 thick ; larger spines of the Mohave form 3 to 5, of the Nevada 

 plant only 1 or 2 inches long. 



-t- -t- Spines, at least the larger ones, transversely ribbed or annulated. 



3. E. viridescens, Nutt. Heads solitary, middle-sized, globose or depressed, 

 with about 13 obtuse tuberculated ribs and a woolly depressed summit : spines 

 stout, reddish, straight or recurved, all annulated, about 12 radiating and 4 (to 6) 

 stouter central ones : flowers greenish (l inches long), with numerous (25 or more) 

 roundish denticulate imbricated sepals on the ovary, as many on the tube, and about 

 the same number of oblong obtuse denticulate petals : stigmas 12 to 15, linear : berry 

 pulpy, green, scaly, with numerous small pitted seeds. Torr. & Gray, Fl. i. 554 ; 

 Engelm. Cact. Mex. Bound. 24, t. 29. 



About San Diego, from the sea-beach to the arid hills and ridges inland ; cultivated in Europe 

 under the name of E. Californicut, Heads 4 to 7 inches in diameter, 3 to 5 inches high, more 

 rarely globose ; woolly vertical area (the youngest growth, where the spines are not yet developed) 

 an inch wide, surrounded by the numerous flowers. 



4. E. cylindraceus, Engelm. Heads middle-sized or large, oval or cylindrical, 

 often proliferous at base, with 21 (to 27) obtuse somewhat tuberculate ribs, and a 

 woolly spineless depressed top : reddish spines all stout and annulated, recurved or 

 flexuous, 12 to 18 exterior, the lowest usually hooked, and 4 very stout central ones ; 

 yellowish flowers 2 inches long, with 40 to 50 rounded fringed sepals on the ovary, 

 and about 25 fringed petals : stigmas and fruit as in the last. Cact. Mex. Bound. 

 25, t. 30. E. viridescens, var. (?) /3. cylindraceus, Engelm. in Am. Jour. Sci. 2 ser. 

 xiv. 338. 



Colorado desert (Palmer, Bischoff), to the eastern slope of the mountains near San Felipe, Parry. 

 Closely allied to the last, from which it is distinguished by its higher growth, more numerous 

 ribs, larger and more numerous spines, and larger flower and fruit. Young plants globose, with 

 fewer ribs ; older ones much higher than thick, 2 or 3 feet high, a foot in diameter, with 20 to 

 nearly 30 ribs ; radial spines 1 or 2, the central 2 inches or over in length ; green berry about an 

 inch thick. * 



5. E. Emoryi, Engelm. Heads solitary, large, globose or oval, with 13 to 20 

 obtuse tuberculated ribs : on the ovate areolae 8 or 9 robust reddish spines, angled 

 and annulated and slightly recurved, a stouter and longer one in the centre, turned 

 downward or more or less hooked : flowers large, purple, with numerous (25) reni- 

 forru ciliate sepals on the ovary and as many spatulate ones on the tube : petals 

 about the same number, lanceolate, laciniate-toothed towards the acuminate tip : 

 stigmas 18 to 20, erect, almost as long as the very robust style. Emory Rep. 156 ; 

 Cact. Mex. Bound. 23, t. 28. 



