14 THE CACTACEAE. 
Au 3. NEOLLOYDIA Britton and Rose, Bull. Torr. Club 49: 251. 1922. 
“Small, more or less cespitose cacti, fibrous-rooted, cylindric, densely spiny, tubercled; tubercles 
more or less arranged on spiraled ribs, grooved above; radial spines numerous, widely spreading; 
central spines one to several, much stouter and longer than radials; flowers large, pink or purple, 
subcentral from axils of nascent tubercles, their segments widely spreading; fruit compressed- 
globose, dull-colored, thin-walled, becoming papery, dry, with few scales or none; seeeds globose, 
black, dull, tuberculate-roughened, with a large white basal scar; embryo straight in typical species. 
Type species: Mammillaria conoidea De Candolle. 
We recognize 7 species from central and northern Mexico and Texas, which have been 
transferred from Echinocactus and Mammillaria. The genus is dedicated to Professor 
Francis EF. Lloyd, whose collections and observations have contributed highly important 
information to our investigations. 
KEY TO SPECIES. 
Plants 3 cm. in diameter or less; central spines sometimes wanting..................... 1. N. pilispina 
Plants larger; central spines always present. 
Central spines curved or hooked........... 0... ccc cee cece c cece cece te eneeenues 2. N. clavata 
Central spines all straight. 
Central spine solitary. 
Central spine stiff, porrect........ 0.0.0... ccc ccc cece e cece eee nenenenees 3. N. horripila 
Central spine weak, ascending or connivent................0 cc cc ceeeueues 4. N. beguini 
Central spines several. 
Spines white or sometimes dark above.......... 0... cece cece cece ee ceues 5. N. ceratites 
Central spines or some of them black. 
Radial spines 25 or more; Mexican species..............0.00cecccueee 6. N. conoidea 
Radial spines 15 or lesS....... 0... ce cece cece cee cece eee eeeeeeeaeas 7. N. texensts 
1. Neolloydia pilispina (J. A. Purpus). 
Mammillaria pilispina J. A. Purpus, Monatsschr: Kakteenk. 22: 150. 1912. 
Plants cespitose, about 3 cm. in diameter; ribs indistinct, made up of very definite, somewhat 
angled tubercles’ young spine-areoles clothed with abundant, long, white wool covering top of 
Fic. 12.—Neolloydia pilispina. 
Fic. 13.—Neolloydia horripila. 
plant ; radial spines 6 or 7, 5 to6 mm. long, 
over top of plant, 2 cm. long or more, whi 
times one; flowers small, 1. 5 to 2 cm. long 
weak and spreading, the upper ones longer and connivent 
te with blackish tips; central spines often wanting, some- 
, purplish; outer perianth-segments brownish. 
Type locality: Minas de San Rafael, San Luis Potosi, Mexico. 
Distribution: Known only from the type locality. 
Figure 12 is froma photograph of a plant collected by C. A. Purpus at the type locality. 
