i68 



THE CACTACEAE. 



"In my garden these plants bloom at irregular intervals for a period of about six months each 

 year. The first flower of the current season opened on May 15 and one is in blossom today, while a 

 number of well-developed buds will open unless killed by unseasonable frosts. The hour of the day 

 that the flower opens varies according to the time that the warm rays of the sun reach the plant. 

 Just as soon, however, as the sun -light leaves the flower, it closes whether it be in the forenoon or after- 

 noon. Clouds obscuring the sun for more than a few minutes or any artificial shade will cause the 

 flowers to close. If conditions are suitable, the flowers will open for three consecutive days, closing 

 each night. The perianth-segments of the flower separate very little. 



"New plants can easily be obtained either by means of seeds or from cuttings. I have been 

 very successful in obtaining cuttings by slicing off the top of a large plant which causes it to bud 

 freely, and these buds can be cut off and will develop into good plants." 



Figs. 182 and 183. Echinocactus grusonii. 



Fifi. 184. Flower of Echino- 

 cactus grusonii. X0.8. 



Echinocereus grusonii azureus is a form incidentally mentioned by Von Zeisold (Monats- 

 schr. Kakteenk. 3: 141. 1893), while Nicholson refers here, as a synonym, Echinocactus 

 aureus (Diet. Gard. Suppl. 334. 1900). 



Echinocactus corynacanthus Scheidweiler and Echinocactus galeottii Seheidweiler (Allg. 

 Gartenz. 9: 50. 1841), while doubtless referable to this genus, are more likely to belong 

 to Echinocactus grusonii than to E. ingens where they are referred by Schumann. 



Illustrations: Monatsschr. Kakteenk. 1:4,7; Gartenwelt 1 : 429 ; Diet. Gard. Nicholson 

 Suppl. 335. f. 356; Cact. Journ. 1: pi. for March; 165; 2 : 42; Wiener 111. Gart. Zeit. 29: f. 22, 

 No. 1; Journ. Hort. Home Farm. III. 60: 144; Journ. Intern. Gard. Club 3: 10; Schelle, 

 Handb. Kakteenk. f. 74; West Amer. Sci. 13: 6; Gartenwelt 7: 277; Mollers Deutsche 

 Gart. Zeit. 25: 474. f. 6, No. 8; De Eaet, Cat. Gen. f. 6; f. 50, No. 1 ; Watson, Cact. Cult, 

 ed. 2. 250. f. 94. 



Figure 182 is from a photograph of a large plant grown by Mr. E- C. Rost at Alhambra, 

 California, photographed by Miles E. Rost; figure 183 shows the flowering top of the plant; 

 figure 184 is from a drawing of a flower from the same collection. 



2. Echinocactus ingens Zuccarini in Pfeiffer, Enum. Cact. 54. 1837. 



Globular to short-oblong, 15 dm. high, 12.5 dm. in diameter (but reported by Karwinsky to be 

 5 to 6 feet in diameter), glaucescent, somewhat purplish, very woolly at the top; ribs 8, obtuse, 

 tuberculate; areoles large, distant, 2.5 to 3 cm. apart, bearing copious yellow wool; spines brown, 

 straight, rigid, 2 to 3 cm. long; radial spines 8; central spine 1; perianth 2 cm. long, 3 cm. broad; 

 inner perianth-segments linear-oblong, yellow, entire, obtuse; fruit ovoid, 3 cm. long, copiously cov- 

 ered by wool coming from the axils of small scales; stigma-lobes brick-red, about 8; seeds large, 

 black, shining, reniform. 



