76 THE CACTACEAE. 



This species differs from Neomammillaria applanata in being less flattened and in hav- 

 ing fewer spines and white flowers. 



Cactus heyderi hemisphaericus, as treated by Coulter, must be a composite, the 

 western and southern forms probably representing different species. 



Illustrations: Cact. Mex. Bound, pi. 9, f. 15 to 17, as Mammillaria heyderi hemi- 

 sphaerica. 



Plate VIII, figure 6, shows a flowering plant from near Brownsville, Texas, collected by 

 Robert Runyon; figure 3 shows a flowering and fruiting plant obtained by Dr. Rose at 

 Laredo, Texas, in 1913, which flowered in the New York Botanical Garden, March 23, 1914; 

 plate VI, figure 2, is from a photograph taken near Brownsville, Texas, by Robert Runyon 

 in 1920. 



11. Neomammillaria applanata (Engelmann). 



Mammillaria applanata Engelmann in Wislizenus, Mem. Tour North. Mex. 105. 1848. 



Mammillaria declivis Dietrich, AUg. Gartenz. 18: 235. 1850. 



Mammillaria texensis Labouret, Monogr. Cact. 89. 1853. 



Mammillaria heyderi applanata Engelmann, Proc. Amer. Acad. 3: 263. 1856. 



Cactus texensis Kuntze, Rev. Gen. PI. i: 261. 1891. 



Plants much flattened; tubercles somewhat angled, their axils naked; radial spines 10 to 18, 

 the radials widely spreading, lower ones darker brown than upper; central spine one, porrect, 

 dark brown; young spine-areoles very woolly; flower-buds pointed, greenish; outer perianth-seg- 

 ments greenish, lanceolate, acuminate margins not ciliate; inner segments 2.5 cm. long, cream- 

 colored, lanceolate, acuminate, with a broad green stripe down the middle; filaments white, shorter 

 than the style; stigma-lobes green; fruit scarlet, naked, 2.5 to 3.5 cm. long; seeds brown. 



Type locality: Rocky plains on the Pierdenales, Texas. 



Distribution: Central and southern Texas. 



The description is based on plants flowering in cultivation. It is one of the earliest 

 species to flower in the spring, beginning soon after the first of March; the fruit requires a 

 full year to mature. 



Mammillaria lindheimeri Engelmann, given by Hemsley (Biol. Centr. Amer. Bot. i : 

 525. 1880) and by the Index Kewensis as a synonym of M. texensis, belongs here. 



Neomammilaria applanata, N. heyderi, and A'^. hemisphaerica are closely related and 

 may represent races of the same species. 



Illustrations: Blanc, Cacti 66. No. 1116; Gartenflora 30: 412; Cact. Journ. i: pi. for 

 March; Meehan's Monthly i: 4; Bait. Cact. Journ. i: 138; 2: 259; Forster, Handb. Cact. 

 ed. 2. 333. f. 35, as Mammillaria applanata; Ann. Rep. Smiths. Inst. 1508: pi. 9, f . i ; 

 Gartenflora 29 : 52, as Mammillaria heyderi; Schelle, Handb. Kakteenk. 263. f. 185; Blii- 

 hende Kakteen i :pl. 43 ; Cact. Mex. Bound, pi. 9, f . 4 to 14, as Mammillaria heyderi applanata. 



Plate IX, figure i, shows a plant in flower and fruit, collected by Dr. Rose on hills 

 above Devil's River, Texas, in 1913, which flowered in the New York Botanical Garden, 

 February 2, 1914. 



12. Neomammillaria phymatothele (Berg). 



Mammillaria phymatothele Berg, Allg. Gartenz. 8: 129. 1840. 

 Mammillaria ludwigii Ehrenberg, Linnaea 14: 376. 1S40. 

 Cactus ludungii Kuntze, Rev. Gen. PI. i: 260. 1891. 

 Cactus phymatothele Kuntze, Rev. Gen. PI. i: 261. 1891. 



Simple, subglobose, glaucous-green; axils of young tubercles bearing white wool, becoming 

 naked; tubercles large, 4-sided; areoles when young white-woolly, in age naked; radial spines 7 to 

 10, grayish white, the three upper smaller, the central (Schumann says i or 2) recurved; flowers 

 described by Schumann as carmine-colored. 



Type locality: Mexico. 



Distribution: Central Mexico. 



We know this species only from the description and illustration. 



