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MIDLAND NATURALIST. 103 
Souris Valley would by character indicate relationship to some 
Rocky Mountain species like 7. Fend/eri, rather than to any mem- 
ber of the genus which is of the remoter Atlantic or Pacific slope of 
the Continent. But 7. Fendlerí has definitely compressed achenes, 
with comparatively thin pericarp, of peculiarly oblique or one sided 
outline; and the nearest kindred of our new type from North Dakota, 
are the species first mentioned. It is not in near contact with 7. 
occidentale, a species of Vancouver Island and adjacent coastal re- 
gions, for that, according to Dr. Gray who first published it, has 
slender achenes a half-inch long. The short plump achenes of 7. 
Lunellii proclaim its nearer affinity for 7. confine of extreme north- 
ern New England; from which the Dakotan species differs by its 
larger, comparatively thicker, and quite turgescent achenes, as well 
as by its ample foliage of large leaflets quite differently cut. 
Thalictrum vegetum nov. sp. 
Planta e grege 7: polygami, ili magis vegeta, licet hu- 
milior. Caulis atrovirens, striatus, fere usque ad inflorescen- 
tian foliosus, apicem versus pilis brevibus plus minus appressis 
sparsim obsitus. Folia caulina ampla, circa 3 dm. longa, petiolis 
leviter, petiolulis magis crebre, hirtellis; foliolà maxima, saepissime 
5—6 cm. longa; circumscriptina late obovata supra medium late tri- 
lobata, lobis obtusis, plerumque integris, mediano interdum inae- 
qualiter trilobo; foliolorum textura membranacea, pagina superiore 
saturate glauco-viridi, sparsim pubigera, inferiore glauca et plus 
minusve tomentulosa. Filamenta alba licet basi capillaria, et om- 
ino pendula; anthera linearia, fere aeque longa ac filamenta, 
acute mucronata: panicula fertilis contracta, ramulis euet caly- 
cibusque pilosiusculis. Achenia immatura breviter hirte 
he specimens of this new ally of 7. polygamum were E TUM 
ed in the years 1902 and 1905, at Devil's Lake, North Dakota, by 
Dr. J. Lunell, who remarks that this plant comes into flower from 
four to six weeks later than the other Thalictra of this region. All 
his specimens were taken in July; and those of the fertile plant 
with fruit not yet mature, were gathered in the middle of that 
month 
The points of contrast btween this and our southern 7. poly- 
&amum are several and well marked. 
The plant of the Middle States and southward, while often 
gigantic in stature—frequently six and seven feet high—is in as- 
