8 AMERICAN MIDLAND NATURALSIT 



crenata, 3-4 vel interdum 5-dentata, basi cuneata vel rotundata, 

 apice brevi-acuminata, appresse et breviter pilosa, denique glabrata, 

 petiolis I -5- 1 -3 longitudinis foliorum ornata sunt. Flores minimi 

 in axillis foliorum congesti, sessiles vel subsessiles, petiolo multo 

 breviores. Calyx dentes lineares tres habet, breviores achaeniis 

 subatris (maturis atris), late ovatis, subplanis, 1.5 cm. longis et 

 latis, acutulis. 



Stem annual, slender, simple, terete, pellucid, almost erect, 

 or ascendent, appressed-hairy or glabrate, 4-8 cm. high, leafy 

 only at the top when young, later with one pair of leaves on or 

 somewhat above or sometimes even below the middle of the 

 stem. These lowest leaves are small, 3-5 mm. transversely, or- 

 bicular or nearly so, with rounded or almost truncate base and 

 quite entire margin, and with petioles as long as the leaves. All 

 the leaves are opposite and petioled, and 2-4 pairs are crowded 

 at the top of the stem, and these are larger, 7-20 mm. long, almost 

 membranous even when fresh, ovate, more or less crenate with 3 to 

 4 teeth, or sometimes 5, cuneate or rounded at the base, with 

 short-acuminate apex, appressedly short-pilose, at length glabrate, 

 3-nerved from the base, the pair of lateral nerves branching out 

 to the lower teeth and ending in the 2nd tooth, with one 

 pair of lateral nerves for the uppermost pair of teeth; petioles 

 1-5 to 1-3 of the length of the blade. Flower clusters small, sessile 

 or subsessile in the axils, and very much shorter than the petioles. 

 Calyx with 3 linear teeth, not as long as the blackish (at full 

 maturity black), broadly ovoid, flattened achenes, which measure 

 1.5 mm. in length and width, acutish. 



This plant may be found on a narrow strip along the boggy 

 margin of a rill, in deep shade, often hidden beneath larger plants, 

 in the woodland of Pleasant Lake, Benson County, North Dakota, 

 and localities with similar natural conditions favoring the growth 

 of this species are very rare within the state. The plants were 

 collected by the writer several times between July 3 and 

 September 2 in the years 1911-12, the latter date furnishing 

 the mature plant which even then, at the close of the season, 

 just immediately before the frost, proved to be of its usual, very 

 small size. 



2. Adicea opaca sp. nov. 



Caulis annuus, simplex, vel ramis brevibus, adscendentibus 

 singulis usque ternis oppositis vel de axillis foliorum orientibus 



