EUPHORBIA, SECTION TITHYMALUS. 139 
E. Parawias Linn., with crowded lanceolate, sessile, fleshy leaves, is 
said to occur as a ballast plant at Girard Point, Philadelphia, Penn. 
(Burk, Proc. Acad. Sci. Phil. 18773 108). 
BIBLIOGRAPHY. 
BAILLON, M. H. Etude générale du groupe des Euphorbiacées 282-7. 
1858. 
BenTHAM & Hooker, Generum Plantarum 8 ;: 260-62, 1880. 
Borssrzr, E. Euphorbieae. De Candolle, Prodromus 15?: 99-175. 
1862, 
CuapMan, A. W. Flora ofthe Southern United States 401-402. 1860. 
Supplement 646. 1883. 
CouLTER, J. M. Botany of Western Texas. Contributions from the 
United States National Herbarium 2; 393-5. 1894. 
ENGELMANN, G. Various papers. See W. Trelease & A. Gray, The 
Botanical Works of the late George Engelmann 434—49, 535. 1887. 
Gray, A. Manual of the Botany of the Northern United States 404-6. 
1848. —vi, 388-9. 1856 [2d ed.].— 433-5. 1867 [5th ed.].— 454-6. 
1890 [6th ed. by S. Watson & J. M. Coulter]. 
HawortH, A. H. Synopsis Plantarum Succulentarum 126-64. 1812. 
Kuiorzscu, F. Linné’s natirliche Pflanzenklasse Tricoccae. Abhand- 
lung der Konig]. Akademie der Wissenschaften zu Berlin. 1859. 
1860. 
Macowun, J. Catalogue of Canadian Plants 424-427. 1886. 
PursH, F. Flora Americae Septentrionalis 2: 606-607. 1814. 
ScHEELE, A. Beitriige zur Flora von Texas. Linnaea 223151. 1848. 
SmaLL, J. K. in N. L. Britton & A. Brown, Illustrated Flora of the 
Northern United States and Canada 2:377-81. 1897. 
Watson, 8. Botany of California 2375-6. 1880. 
EXPLANATION OF PLATES. 
The habit drawings, except in plates 48, 51 and 52, 
drawn by the author, were made from herbarium speci- 
mens by Mrs. Grace Johnson Vieh under the supervision 
of the author. The details were drawn by the author, in 
most cases with a camera lucida, and will show the most 
important characters of each species. Unless otherwise 
indicated the details are enlarged five diameters, except 
those of the seeds, which are enlarged eight diameters. 
The habit drawings are reduced one-half. 
Plate 11, H. Lathyris.— 1, Involucre, glands, and staminate pedicels 
and bracts; 2, ventral view of seed; 3, lateral view of caruncle. 
DD 
