222 COMPOSITjE. (composite family.) 
oblong, clothed with hooked prickles so as to form a rough burr, 
2-celled, 2-flowered ; the flowers consisting of a pistil with a slen¬ 
der thread-form corolla. Achenia oblong, flat; destitute of pap¬ 
pus. — Coarse and low annuals, with branching stout stems, and 
alternate toothed or lobed petioled leaves. (Name from £dv6os, 
yellow, in allusion to the color the plants are said to yield.) 
* Leaves heart-shaped , rounded , not spiny at their base ; fruit (involu¬ 
cre) terminated by 2 stout beaks. 
1. X. Struma rill 111 , L. (Common Cockle-burr.) Fruiting 
involucre oval , rather pubescent , the beaks straight ; leaves 3-5-lobed 
and cut-toothed ; lobes acute. — Var. Canadense has mostly larger 
involucres than the introduced plant, more rough and prickly ; the 
stem spotted. — Waste places. July-Sept. — The var. is native in 
the West. A vile weed. 
2. X* ecliinatum, ^Murray. (Sea Cockle-burr.) Fruiting 
involucre oval , very thickly beset with rigid slender prickles which are 
strongly bristly , as well as the incurved beaks; stem and stalks rough, 
spotted ; leaves obscurely lobed or toothed. — Salt marshes, Massa¬ 
chusetts to N. Jersey and southward. Aug. - Oct. — Ripe involucres 
H' long, thick and turgid. 
* * Leaves narrowed into the petiole , furnished with 3 slender yellow 
spmcjr at the base , fruit tipped with a single inconspicuous beak. 
■ X* spinosum, L. (Thorny Clot-burr.) Leaves ovate- 
nceolate , pointed , wedge-shaped at the base, entire, or slightly 3-lob- 
ed, hoary underneath; stem much branched. — Waste places, intro- 
uced and naturalized along the seaboard. Sept. — Nov. 
Subtribe 2. HELIANTHEJ2. — Heads radiate, or rarely 
discoid ; the disk-flowers always perfect and fertile. Receptacle 
chaffy. Anthers blackish, not tailed at the base. Pappus none 
or crown-like, or of one or two chaffy awns, never capillary or of 
uniform chaffy scales. Leaves chiefly opposite. (Genera 30-35 
and 38 have the achenia flattened laterally if at all: genera 36 and 
37 have them flattened parallel with the scales of the involucre.) 
30. HELIopsiS, Pers. Ox-eye. 
Heads many-flowered ; the rays 10 or more, fertile. Scales of 
the involucre in 2 or 3 rows; the outer leaf-like and somewhat 
spreading, the inner shorter than the disk. Receptacle conical: 
chaff linear. Achenia smooth, 4-angular. Pappus none, or a 
mere border. — Perennial herbs, like Helianthus. Heads showy, 
