— 433 — 
that the identifications of the stems by these authors were in part 
erroneous, or that, as Seward (41) remarks, it is impossible to define 
the distinctive characters of Phyllotheca and Schizoneura in the 
absence of leaves. 
The Brazilian material is especially interesting, however, since two 
of the specimens offer stem or branch bases. That shown in Fig. 3 
exhibits a basal stem fragment about 10cm in length. The base, 
which is not well shown in the photograph, is conical, with strongly 
convex borders anda blunt point. The lowest distinct internode is 
but 3.5 mm in length, the ribs being 2.25mm in width. Nine 
successively elongating intervals are lo be observed. From one of 
the nodes, midway up the fragment, a large branch arises on the 
right, with base broadening out rapidly from a rather narrow point 
of connection in typical Calamarian form. The ribs on this branch, 
the full width of which is not seen are a little more than 2mm 
broad. 
The conical form of the base of the stems or branches is better 
shown fromasmaller fragment in Fig. 4 Here,as well as in many 
of the fragments of large stems, we havea form of cast, directly com- 
parable, even tothe nerve tubercles, with the Northern Calamarian 
forms, such, forexample, as the common Calamites Suckowitt. 
The close relationship of Phyllotheca to the typical Calamarian 
stock is further shown by the structure of ils slrobilus which has 
been found tobe similar to that of Calamostachys. 
It is possible that the slender stem fragment, Pl. V, Fig. 6, placed 
with doubt under Schizoneura may really belong tothe same genus as 
do the large stems just described. 
Localities : Northeast of Minas, Santa Catharina. Beds 55 meters 
above the granite, or 225 meters below the Iraty black shale, Lots 
3586 and 3921. 
Schizoneura 
Schimper and Mougeot, Monogr. pl. foss. gres bigarré Vosges, 1844, 
p. 48. 
The genus Schisoneura contains ramose Equisetaceous forms 
specially characterized by the complete union of the leaf, and the 
(A) Loc. cit., p. 325, 
