1 68 THE CACTACEAE. 



MamiMILLARIa loricata Martius in Pfeiffer, Enum. Cact. 13. 1837. 

 Echinocactus loricaius Poselger, AUg. Gartenz. 21: 107. 1853. 

 Coryphantha loricata Lemaire, Cactees 35. 1868. 

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



Solitan', simple, globose, 4 to 5 cm. in diameter, glaucous-green ; tubercles short-ovate, 4-angled 

 at base; radial spines 12, spreading, rigid, yellow, 6 to 8 mm. long; central spines 2, stouter than 

 the radials, S to 10 mm. long, black at tip, the upper one straight, the lower one curved; flowers and 

 fruit not described. 



This plant is recorded as of Alexican origin, but we have found no description of it 

 subsequent to the original and it may never be identified. Forster referred it to Mammil- 

 laria polythele, but Schumann did not know it. 



Mammillaria heteracantha was referred here as a sjoionym by Pfeiffer (Enum. Cact. 

 13. 1837). This plant was mentioned by Martius (Verz. Konig. Bot. Gard. Miinchen 

 127. 1829), but so far as we can learn was never described. 



Mammillaria monocentra Jacobi, Allg. Gartenz. 24: 90. 1856. 



Depressed-globose, up to 12 cm. high, about 8 cm. in diameter, umbilicate at apex; tubercles 

 milky, somewhat rhomboid afbase, a little flattened, not setose in their axils; radial spines 6, 

 white with black tips, a little spreading; central spine solitary, stouter and longer than the radials, 

 about 2.5 cm. long; flowers rather large, rose-colored; style rose-colored; stigma-lobes 6, reddish 

 yellow. 



Jacobi referred this plant, presumably of Mexican origin, to the group Angulosae- 

 tetragonae of Salm-Dyck. 



Schumann placed it among his list of little-known species ; we know it from descrip- 

 tion only. 



Mammillaria nervosa cristata Joum. Hort. Home Farm. iii. 60: (?) 7. 1910. 



We know this plant only from a brief description and an illustration on pages 7 and 

 8 of the journal here cited: 



"Mammillaria nervosus cristalus* grows in convoluted sinuous masses like a great brain-mass. 

 The gro\vths are covered with spiny mamillae (whence the name of the genus) and are of a dull 

 olive-brownish hue. It, too, is Mexican." 



We are not able to place this plant ; it resembles the cristate form sometimes assumed 

 by Pediocactus simpsonii and also resembles MammUlaria bicolor as shown by the illustra- 

 tion under M. daedalea. 



Illustration: Joum. Hort. Home Farm. iii. 60: 8 (or 7). 



Mammillaria nicholsoni Joum. Hort. Home Farm. in. 60: 7. 19 10. 



We know this species only from the illustration referred to below and the following 

 brief note taken from the place of publication : 



"Mammillaria nicholsoni resembles several of the Echinocactuses in external form. It was 

 named we believe in honor of the late ISIr. George Nicholson and came to Kew from the Swanley 

 Collection. All our illustrations were secured at Kew where the collection is well cultivated. M. 

 nicholsoni forms spherical masses with the tj'pical protuberances or tubercles, these being tipped 

 with sharp spines." 



It is doubtless of Mexican origin. 



Illustration: Joum. Hort. Home Farm. iii. 60: 9. 



Mammillaria nuda De Candolle, Prodr. 3: 460. 182S. 



This is based on Cactus nudus (Mociiio and Sesse, PL Mex. Sc. ined.) , but has never been 

 subsequently identified. It was also taken up by Otto Kuntze as Cactus nudus (Rev. Gen. 



* This is the original spelling. 



