II4 THE CACTACEAE. 
> 69. Neomammillaria aureiceps (Lemaire). 
>Mammillaria auretceps Lemaire, Cact. Aliq. Nov. 8. 1838. 
Mammillaria rhodantha aureiceps Salm-Dyck, Cact. Hort. Dyck. 1844.7. 1845. 
Cactus aureiceps Kuntze, Rev. Gen. Pl. 1: 260. 1891. 
Globose to short-oblong, 8 to 10 cm. in diameter; tubercles short, terete in section, woolly and 
setose in their axils; radial spines about 20, bristle-like, white, 5 to 8 mm. long, spreading; central 
spines several, sometimes as many as 9, yellow, stouter and longer than the radials, 10 to 14 mm. long, 
somewhat spreading and a little curved inward; flowers small, dark red. 
Type locality: Mexico. 
Distribution: Valley of Mexico. 
Our description is based on specimens recently sent us by Dr. Karl Reiche as Mam- 
millaria rhodantha, under which name it usually passes. M. rhodantha, however, has dif- 
ferent spines and is more strictly a mountain species. 
Plate 1x, figure 3, shows a plant sent from the Edinburgh Botanical Garden in 1902 as 
Mammillaria rhodantha which flowered in the New York Botanical Garden, October 15, 
1912. Figures 117 and 118 give two views of this plant sent us by Dr. Reiche from the 
Valley of Mexico. 
Fic . eye . 
IG. 119.—Neomammillaria yucatanensis. 
Fic. 120.—Neomammuillaria ruestii. 
70. Neomammillaria yucatanensis sp. nov. 
_ Plants in clumps of 4, erect, cylindric, not milky, 10 to 15 cm. long, 3 to 6 cm. in diameter, very 
spiny ; tubercles conic, woolly in their axils but not setose; radial spines about 20, white, spreading, 
acicular; central spines 4 or rarely 5, much stouter than the radials. 6 to 8 mm long slightly spread- 
ing above, yellowish brown; “‘ flowers very small, rose; fruit oblong, bright red.” 
Collected by George F. Gaumer at Progreso, Yucatan, Mexico, in 1918 (No. 23939) 
and again in 1921 (No. 24367, type). 
We have not seen this species in flower or fruit but Dr. Gaumer has described them as 
abov e. He Says that the plant is rare on the land side of the coastal marshes. 
Figure 119 is from a photograph of the plant sent in 1921 by Dr. Gaumer. 
