142 THE PALEONTOLOGY OF MINNESOTA. 
|Phyllodictya. 
PuHyLuopicryaA FROoNDOSA 2Ul/rich. 
(Not figured,) 
Phyllodictya frondosa ULRicu, 1882. Jour. Cin. Soc. Nat. Hist., vol. v, p. 174, pl. 8, figs. 11. Na 
and 11b. 
The name of this species occurs in the list appended to my preliminary report 
on the Minnesota Bryozoa (Fourteenth Ann. Rep. Geol. Surv. Minn., p, 102; 1886). 
The identification was based upon several small fragments, none of them in a con- 
dition to afford satisfactory thin sections. Nor did any of the more numerous and 
larger specimens of Phyllodictya collected subsequently for my own cabinet by Mr. 
Charles Schuchert and others, as well as by myself, prove any better for that purpose. 
I was, therefore, unable to verify the identification until last year, when I detected a 
single well preserved fragment, about 15 mm. square, in a lot of fossils kindly given 
me by Prof. C. W. Hall, of the State University. Both the superficial and internal 
structure of this specimen, which was obtained too late to appear on the plates, 
agrees closely enough with that of one of the original Kentucky types of the species. 
Ordinarily, this would be quite sufficient to establish the identification of a species, 
but in this case, a fact about to be mentioned causes me to use the question marks. 
Recently I had occasion to prepare a set of thin sections of a specimen supposed to 
belong to this species. These seem to differ so much from the original set, that one 
of two things is evident: either I included two species in my original diagnosis of 
P. frondosa, or the species is more variable in its internal structure than I supposed. 
It is probable that the differences observed are only the result of age, but as I have 
not had time to make the sections necessary to prove this, I thought it best to men- 
tion the difficulty, leaving its removal to some future time. Before giving the fol- 
lowing brief description of the Minnesota specimens, it would be well to mention 
that the one received from Prof, Hall agrees best with the specimen represented by 
fig. 11 of the original work on the species, while the resemblance to the specimen 
that furnished the original thin sections and the enlarged surface view is much 
less.* Also, that I now believe that none of the specimens catalogued by me in 1886 
as P. frondosa really belong there. Most of them, perhaps all, are to be referred to 
the new species P. varia. 
Zoarium leaf-like, 1.5 mm. thick; size unknown, only fragments having been 
seen. At intervals of 3 or 4 mm. the surface presents smooth or grano-striate 
solid spots, 1 mm. or more in diameter. These spots may be on a level with the 
general plane of the surface, or slightly depressed. Zocecial apertures ovate, a little 
*The new set of sections were prepared from an example like the first, 
