270 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiv. 
fore appear, in the absence of distinctive sponge characters, to be 
unwarranted at present. 
It nia}" not be improper in this connection to add that certain of the 
organisms generality though doubtfully ranged with the Graptolites 
might be more at home among the alg?e.^ 
Among other living alga^ whose form is comparable to that of 
Buthotrephis, though agreeing less closel}' in texture, the genus Lia- 
gora (Z. corymhosa J. Agardh) may be mentioned, while among the 
fossil types fronds resembling in a general way those under consider- 
ation are found among the abundant Eocene species of Chondrites^ 
some of the remains of which are rather densely carbonaceous.^ 
EXPLANATION OF PLATES XVI-XVIII. 
BUTHOTREPHIS FROM THE EURYPTERID (rONDOUt) BEDS AT KOKOMO, INDIANA. 
Plate XYI. 
ButhotrepJrs diraricata David White. Natural size. Collection of C. E. Newlin, 
Irvington, Indiana. 
Plate XVII. 
Buthotrephis newJhv David White. Natural size. a. Enlarged detail showing fila- 
mentose texture (x4). Collection of the U. S. National Museum. Cat. No. 8175, 
IT.S.N.M. 
Plate XVIII. 
Buthotrephis nen'lini David White. Form with narrow thalli. Natural size. Col- 
lection of C. E. Newlin, Irvington, Indiana. 
^The texture of the forms from Kokomo and the Buffalo Waterlime appears to have 
much in common with some of the specimens now resting in or near Inocaulis. 
'^ See Chondrites dolichophyllus Squinabol, Contrib. Fl. foss. Terz. Liguria, pt. i, 
Alghe, pi. B. 
