10 Bulletin Wisconsin Natural History Society. [Vol. 6, Nos. 1 — 2. 
plants from so low a horizon, with which it may be compared — 
Cordaites and Nematophycus. 
With respect to the former, although at least four species are 
known to the Middle Devonian^, there are none which may be 
directly compared with the present specimen, either in external 
appearance or in mode of preservation, and it is permissible to 
exclude the genus from further consideration, without hesitation. 
Nematophycus crassus is known to the Hamilton Group of 
New York-. So far as the general mode of preservation may be 
taken as evidence, that presented by the Berthelet specimen is in 
exact accord with what is commonly found. Furthermore, the 
condition in which the plant is found, indicates clearly, that it was 
soft in texture and very susceptible to decay which had progressed 
extensively before infiltration. 
The absence of hapteres and other portions of the anchorage 
system, cannot be adduced as evidence opposed to the view that 
this may have been a large alga, since such an objection would be 
equally valid as applied to Cordaites. All the evidence points with 
directness and force, to the idea that the plant is a species of 
Nematophycus, but which of the known species it is impossible 
to determine in the absence of internal structure. 
So far as known, N. crassus is the only species found in the 
Hamilton Group, and it must have had a very extensive distribu- 
tion in Middle Devonian time. It is, therefore, in a high degree 
probable that the New York specimens and those from Milwaukee 
represent the same species. It would seem better, however, to in- 
dicate the latter by a distinctive name derived from the locality, 
until such time as further and more complete material may enable 
^ North American Species of Dadoxylon. Trans. E. S. C, VI, 1900, 
iv, 51-97. 
Ann. Bot., X, 1896, 47. 
Proc. U. S. Nat. Mns., 929, 1893, 115-118. 
Trans. S. C, VIT, iv, 23. 
