14 CORRECTIONS. 
Page 6, line 29, after hilum omit —. 
Page 7, line 7, for umbillicus, read umbilicus. 
Page 7, line 15, after dilatatis put ;. 
Page 7, line 28, for tuberculata, read tuberculosa. M. Grahami is nearly allied to M. Schel. 
hasti, Pfr., from Real del Monte, Mexico. The next species, @. Wrightii, is closely allied to 
M. zephyranthoides, Scheidw., from Oaxaca, Mexico ; without the flower, however, and especially 
without the fruit and seed, which latter has never been paid attention to. These plants can 
scarcely be sufficiently well characterized, nor their relationship ascertained. 
Page 8, line 19, for Goopricuir, read Goopripalr. 
Page 9, line 28, for interior, read exterior. M. sphaerica is almost too closely allied to the 
Mexican YU, longimamma, DC. 
Page 10, line 41. The plant here described as a variety exactly agrees with some original 
specimens of M. Scheerii preserved in the collection of Prince Salm-Dyck. It will not be 
useless here to urge the importance of preserving the dead cactus plants, or, as these specimens 
are fancifully called, the ‘‘ skeletons.’’ I have been materially assisted by being able to 
examine the skeletons of some authentic original specimens, of which no living ones are now 
found in the gardens. But generally the dead plants are thrown aside, and a description, often 
vague or incomplete, or at best an indifferent figure, is all that is left for future identification. 
Unscrupulous gardeners and traders do their best to increase the confusion, 
Page 11, line 7, for mucranatis, read mucronatis. 
Page 12, line 9, for last, read next. UM. pectinata is probably not sufficiently distinct from 
M. radians, DC., and with it, and both the following species, M. Echinus and M. scolymoides, 
may belong to M. cornifera, DC., the two former being the forms without, and the three latter 
those with, central spines. 
Page 14. WV. scolymoides. A specimen brought by Dr. Bigelow has flowered. The flower 
greatly resembles that of MZ. pectinata, figured on plate 11, but is more of a reddish than yellow 
tinge. Dr. Poselger assures me that they also vary with white or whitish flowers. M. tuber- 
culosa is clearly identical with 1, strobiliformis, Scheer in Salm, Hort. Dyck, (1850,) as I have 
ascertained by a careful examination of the original specimen (now dead) in the collection of 
Prince Salm. Mr. Scheer’s name, having the priority, must be substituted for mine. 
Page 14, line 26, for X., fig. 1-6, read XXIT., fig. 1-16. 
Page 15, line 9, for 18, read 22. 
Page 15, line 15, for interior, read exterior. 
Page 16, line 5, for tulis, read patulis, 
Page 17, line 9, for spine, read spines. M. heteromorpha, Scheer in Hort. Dyck, 1850, is the 
same species, to judge from the “ skeleton’’ of the original specimen in Coll. Salm. Anhalonium. 
ie aaa e meer ae eicteo Anhalonium will probably better be kept 
into ribs, would comprise ey Willink ‘ priser econ licngerey oe 
» Lem. The tufts of dense wool on this plant 
= at represent the (absent) spines, but are axillary productions, surrounding and partly 
ang the flower and fruit. The ovary is perfectly naked, as in other Anhalonia or Mamii- 
tae . aoe ee — _— antoresting Leuchtenbergia Principis, 
a third section of this genus. The flowers being 
Lactiny just below the tip of the nascent tubercles, (which, when full grown, are three to six or 
