170 
VINE: CAKBOKIFEKOUS POLYZOA. 
not certain that the British species is not identical with it. For the 
present it may be as well to retain them separate, because there are 
still some features in the Scotch that I have not as yet detected in 
the Derbyshire species. The general habit of the two is similar ; 
the arrangement and character of the cells is the same ; it is only 
in the superficial tubercles that there is a difference. 
Localities : Castleton, Derbyshire ; Settle and Richmond, 
Yorkshire. 
Genus THAMNISCUS, King. 
Branches free, round, frequently and regularly bifurcating ; 
more or less in one plane ; Zoaecia on one side, cells immersed, round, 
arranged in oblique lines. 
9. Thamniscus dubius? King, Permian Foss., p. 44, pi. Y. T. dubius , 
(Shrubsole) Paper on Thamniscus, Quart. Jour. Gtol. Soc. August, 1882. 
Var. Carbonarius, new var. 
Zoarium , a series of flattened branches generally in one plane. 
Branches free, frequently dividing, measuring about half a line in 
breadth, equal in size along their whole length. Zocecia on one 
side of the branch, apertures circular arranged in lines, or obliquely ; 
about six cells in one line measured longitudinally, from four to six 
rows in the width of branch. 
Localities: Castleton, Derbyshire ; Settle, Yorkshire (small 
fragments). 
There is a very great difference between the above species and 
that described by Mr. John Young, as occuring in the Carboniferous 
rocks of Scotland. Thamniscus ? RanJdni , Young (Ann. Mag. Nat. 
Hist., May 1875), is of uncertain affinities ; for as Mr. Young remarks 
“ Meanwhile though strongly disposed to regard this fossil as a true 
Ilornera , or a member of a closely allied genus, we think it safer to 
leave it in the Palaeozoic genus Thamniscus .” The Scotch type 
may be ultimately placed in the genus Hornera ; but the present 
form has not the least affinity with that or any genus related to 
Hornera. I have named the species as a variety of T. dubius out of 
deference to Mr. G. W. Shrubsole, whose paper on Thamniscus , 
Silurian, Carboniferous and Permian {Quart. Jour. Geol. Soc ., Aug. 
1882), merits this special approval. In that paper the whole history 
