367 
Cephaluros mycoidea and Phyllosiphon sp., two Parasitic Alga, 
new to North America, by W. T. Swingle. 
An Analysis of the Conditions affecting the Distribution of 
Plants, by Frederick V. Coville. 
A Sclerotium Disease-of Plants, by P. H. Rolfs. 
Notes on Reséelia pyrata, by L. H. Pammel. 
Crossing of Cucurbits, by L. H. Pammel. , 
A case of poisoning by the Wild Parsnip, Cicuta maculata, by 
L. H. Pammel. , 
Ulota Americana, Mitten, and Orthotrichum Americanum, 
Beauv., by Elizabeth G. Britton. 
Paleobotanical Papers read before the Section of Geology and 
Geography, A. A. A. S., Madison, Wisconsin, 1893, 
PAPERS BY Jos. F. JAMES. 
“ Remarks on the Genus Arthrophycus.’—Attention is called to 
the fact that this organism was originally described by Harlan in 
1831, under the name Fucoides Alleghaniensis. In 1838 Conrad 
changed it to Lucoides Harlani, and when, in 1852, Hall changed 
the generic name to Arthrophycus, the specific name given by 
Conrad was retained, and this is the one under which it has been 
generally known. In accordance with the rules of priority, it 
should appear as Arthrophycus Alleghaniensis (Harlan). 
“ Studies in Problematic Organisms; the Genus Fucoides.’—A 
revision of the classifications under which various problematic 
organisms have been placed in the attempt to differentiate them 
or to identify them with living alge genera. The author outlines 
a new scheme of classification based upon recent researches, 
which have proved many of the so-called algz to be inorganic 
markings, tracks of animals, etc., and have also added to the more 
€xact determination of the affinities of many which are true alge. 
“ The Value of Pseudo-alge as Geological Guides.’—The author - 
oncludes that, inasmuch as the evidence of the organic nature of 
Many of the so-called fossil alge is defective, any deductions 
based upon the presence of many described species are valueless 
and misleading, and that they are not safe geologic guides. 
