ORDER 101—MARVELWORTS. 275 
COHORT III. 
THE APETALOUS EXOGENS. 
Essential Character.—Flowering plants (Puayocamta), 
with their stems growing by additions to the outside and the 
wood in circular layers (Exogrns), with the seeds inclosed in 
seed-vessels (Anerosrerms), and the flowers destitute of petals 
(APETALZ). 
Orver C.—ARISTOLOCHIACE. Birthworts 
Low herbs or climbing shrubs with alternate leaves, large flowers ; 
calyx adhering to the ovary, valvate in bud, brown or dull colored; 
stamens 6-12, at top of the 6-celled, many-seeded ovary. 
Analysis of the Genera. 
Calyx bell-form, regular, 8-cleft. Stamens 12. Herbs with creeping, 
underground stems. Wild Ginger. Asa’rum, 1 
Calyx tubular, bent, irregular, Anthers 6. Shrubby, erect or climbing, 
with very odd flowers. Birthwort. ArisToLo’on1a, 
ASARUM. Wild Ginger. 
1 A Canadense. Canada W. Leaves in pairs, broad-reniform, with the single flower 
between the petioles scarcely above-ground. May-July. c. 
2 A.Virginicum. Virginia W. Leaf solitary, round-ovate, cordate, the single flower 
much shorter than the petiole. Sepals obtuse. Mts. Va.S. April. 
8 A. arifol’iam. Arwm-lv. W. Leaf solitary, broadly hastate, with long, angular 
lobes at base. Calyx throat contracted, lobes very short. Va. 8. April. 
Orver CI.—NYCTAGINACE.Z. Marvelworts. 
Herbs (shrubs or trees) with swelling joints; entire, opposite leares ; 
flowers surrounded by an involucre (which is, of course, calyx-like when 
the flower is solitary) : 
calyx often colored like a corolla, tubular or funnel-form, breaking off 
above the 1-colled, 1-seeded ovary. 
