contributions to north american 

 euphorbiace;e-vi 



CHARLES F. MILLSPAUGH, M. D. 



Chamaesyce S, F. Gray, Nat. Arr. Brit. PL 2:260. 1821. 



Leaves opposite, inaeqtiilateral; inflorescence solitary or capitulate, 

 axillary and terminal; bracteoles plumose or ciliate; seeds minute, 

 ovoid or elongate-ovoid, more or less quadrangular the facets smooth or 

 transverse-rugulose . 



Type species: Euphorbia peplis Linn. Sp. PI. 652. 1753. 



Chamaesyce barbicarina sp. nov. 



Plants semi-erect, about 2dm. high, annual. Stems many, from a 

 but slightly raised rootstalk ; branches many, virgate, terete, long-pilose 

 especially upon the upper surface. Inflorescence solitary in the axils 

 of the terminal branchlet leaves. Leaves opposite, 5-8 x 2-4mm., 

 ovate, obtuse, broadest at the roimded apex, base strongly auriculo- 

 oblique, glabrous the thickened margin crenate-dentate; petioles about 

 I mm., hairy; stipules broadly triangular-lanceolate, lacerate. In- 

 volucres turbinate, glabrous without and within; peduncle about the 

 length of the involucre (in fruit twice the length); involucral lobes 

 triangular, ciliate; siilcus shallow; glands scutelliform; appendages white, 

 irregular-ovate, margin crenate or 2-3-crenate-dentate; bracteoles none; 

 male pedicels few, short; female pedicel ciHate-hairy; styles short, 

 bilobed at the apex. Capsule obpyriform, glabrous except on the blunt 

 keels of the otherwise smooth carpels which are long-ciliate fringed; 

 seeds red, ovoid, acute, .9 x .6mm., angles sharp, facets marked by a few 

 very slightly raised irregtilar and broken transverse ridges. 



Between Ch. dioica and Ch. yucatanensis but readily distinguished 

 from both by the peculiar ciliate-fringed keels of the carpels. 



Sitilpech Road, November, 1895, Gaumer 939a (Type sheet, 

 Field Mus. cat. no. 196,352.) It was gathered as a part of a mass of Ch. 

 rutilis by the collector. Also collected at Chichankanab, Gaumer 1432, 

 2074; and at Pocoboch 2405. 



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