29 
This was the plant which first aroused my interest in the 
prickly-pears of Florida, and one of the more striking characters 
it exhibited was the numerous tuberous roots. For some time 
it was thought that this character was peculiar to Opuntia 
austrina, but later investigations have shown that Opuntia 
Pollardi, O. ammophila, and O. Drummondi produce tuberous 
roots; but none of them to the extent that the species under 
consideration does. 
Opuntia austrina is a short-lived plant. Every year or two 
the individual plants break down and new ones start afresh 
either from the tuberous roots or from the old joints. It may 
be that there is some relation between the fibrous and tuberous 
rooted species and longevity. At any rate, the plants with 
fibrous roots seem to be longer lived as individuals than those 
with tuberous roots. 
’4. Opuntia ammophila Small, sp. nov. 
Plant erect, more or less branched throughout or ultimately 
with a stem 1-2 m. tall or more, becoming 1-2.5 dm. in diameter, 
bearing several spreading branches near the top, thus tree-like, 
tuberous at the base: joints various, those of the main stem 
elongate, ultimately fused on the ends and subcylindric, those 
of the branches typically obovate or cuneate, varying to elliptic 
or oval, thickish, o. 5-1.7 dm. long, becoming gray-green: leaves 
stout-subulate, 6-10 mm. long, green: areolae relatively numer- 
ous, conspicuous on account of the densely crowded long bristles, 
especially on the older joints, the marginal ones, at least, armed: 
spines very slender, solitary or 2 together, reddish or red, at 
maturity gray, mostly 2-6 cm. long, nearly terete, scarcely 
spirally twisted: flowers several on a joint: sepals lanceolate, 
acute or slightly acuminate: buds sharply pointed : corolla bright- 
yelow, 5-8 em. wide; petals cuneate or obovate, notched and 
prominently apiculate, scarcely erose: stigmas cream-colored: 
berries obovoid, 2-3 cm. long, more or less flushed with red- 
purple, many-seeded : seeds about 4mm.in diameter. [Plate 224.] 
Inland sand-dunes (scrub), peninsular Florida.—Type speci- 
mens from south of Ft. Pierce, collected in December, 1917, by 
JK. Small. They are in the herbarium of the New York ene 
cal Garden, Living plants are also in the conservatories of the 
Garden, as well as in the plantation at Buena Vista, Florida. 
