Synopsis of North American Amaranthacee. IT.* 
EDWIN Bb. ULINE AND WILLIAM L. BRAY. 
ACNIDA: L.Sp.. Pl.2027-:1753- 
Flowers completely dicecious, the pistillate ones without 
calyx, the staminate ones with 5 equal oblong sepals and 5 
stamens: otherwise like Amaranthus. 
At the time of the publication of Linnzus’ Species Plant- 
arum, but a single species of this genus was described, 
namely, A. cannabina. The specimen was collected in Vir- 
ginia and was described in 1741 by Dr. John Mitchell under 
the generic name Acuide. Dr. Gray in his revision of the 
genus?” states that ‘‘on the whole our botanists have failed to 
make out more than one species,” although Moquin-Tandon 
had already described A. rusocarpa. Dr. Gray set up three 
sections: (1) EUACNIDA, in which he sets apart A. rhyssocarpa 
(A. rusocarpa Moq.) and adds A. australis (A. cannabina 
Chap.); (2) MONTELIA Mogq,, characterized by its indehiscent 
utricles, including A. ¢uberculata; (3) PYXIDI-MONTELIA, 
including A. tamariscina (Amarantus tamariscinus Nutt. and 
Montelia tamariscina Gray, in part). 
With the increasing knowledge of the geographical distri- 
bution of the species, and with the considerable additions to 
herbarium material since Dr. Gray’s revision, most of which 
we have seen, it seems best to indicate a somewhat modified 
disposition of the species. On the basis of geographical dis- 
tribution, two very natural groups present themselves, those 
of the salt marsh and coast region of the Atlantic, and the 
inland and western forms. The former embraces Gray’s 
EUACNIDA and A. Floridana Watson. Of the three species 
referred by him to this section, we believe that A. cannabina 
and A. rusocarpa are not distinct. We find here a complete 
series of intergradations, while the difference of age actually ac- 
counts for more than the difference called for in their original 
delimitation. The third species of EUACNIDA, A. australis, 
Shows no specific departure from the others, but its range is 
_ The first number of this series, presenting the genus Amaranthus, was pub- 
lished in Bor. Gaz. 19: 267, 313. 1894. 
Am. Nat. 9: 487. 1876. 
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