—62— 



openings, the central occupying about Y> the total diameter; 

 there is also a row of yellow cells separating the carinal from the 

 vallecular cavities. Fruiting most abundantly in June, but may 

 be found after that sparingly through the summer. 



HABITAT. 



As the name indicates, this species thrives in swampy places. 

 It grows best in damp meadows amongst grass, but also in deep 

 swamps, in sour soil, in sandy places with damp subsoil; also in 

 damp woods with E. arvense, from which Milde says it is often 

 hard to distinguish, even by an expert. Usually densely gregari- 

 ous, it becomes scattered in grassy places and amongst bushes, 

 where it often climbs by means of excessively elongated branches. 



The American plant usually has a different aspect from the 

 European, the sheaths and teeth of the branches are longer, the 

 latter more acute, the roughness of the branches is less disposed in 

 cross-bands, and various other minor differences might be noted, 

 but hardly enough to justify its erection into a geographical 

 variety, at least until the differences are found to be constant. 



Abundant in Europe from the farthest north to 44 50' ; 

 rarely found in America. It,has been seen by me from the fol- 

 lowing places: ' Maine — VanBuren, Fernald ; New Hampshire — 

 Manchester, F. W. Batcheldcr ; Vermont — Burlington Bay, 

 Grout, Eggleston; near Sorel river— Pringle; Connecticut— 

 Selden's Cove, Lyme, under influence of tides — C. B. Graves; 

 New York — Buffalo, Clinton ; Illinois — Peoria, Brendel ; Wash- 

 ington — Columbia river, Suksdorf; Tacoma, Flett; British 

 Columbia— New Westminster, Hill; Alaska — Popoff I., D. A. 

 Saunders ; Arakamtchetchene I. — Behring Straits, Wright; Al- 

 berta — Banff, Macoun; Ontario — Lake Nipigon, Macoun ; Sas- 

 katchewan — Red Deer river, Macoun. Found also in New- 

 foundland and about Hudson's Bay. Minnesota localities need 

 verification. Has been reported from Arizona, but probably a 

 variety of la'vigatum has been taken for it, as the branches 

 have a very similar appearance under the lens. 



The Indians of Alaska make baskets of the rootstocks of an 

 Equiselum. In the absence of the aerial portion it is impossible 

 to diagnose these with certainty, but there is little doubt that 

 this is the species employed, although specimens submitted to me 

 were of the unprecedented thickness of one's finger. 



This species has no near relatives. In the structure of the 

 stem, especially in section, it greatly resembles Arvense; but as 



