138 TJic A/ncrica/i Geologist. Septtnibci-, i9to 
on the radial lines, and none/of them at the angles. I have 
given a figure of the other specimen, which shows the struc- 
ture much better, natural size, and one plate with parts of con- 
tiguous ones, enlarged 4 diameters (PI. XVI, figs. 9, 10). I 
have three other specimens of this species which show the 
same structure. 
After having referred to our figure 2b for the correct pos- 
ition of the supposed pores, Mr. Bather next invites the im- 
partial reader to "examine a few hundred specimens of fistu- 
late genera, and he will find that the apparent pores or slits 
never are on the radial lines, but always at the angles or be- 
tween the ridges of the folded plates." Where such wealth 
of material is to be found, tO' enable the student to examine 
specimens of fistulate genera preserving the ventral sac by 
the few hundreds, I do not know. The Wachsmuth and 
Springer collection has been supposed to be pretty well pro- 
vided with structural specimens, culled from the largest col- 
lections ever made at the best localities for this purpose, but 
I cannot lay claim to such multitudes. I must be con- 
tent to number those exhibiting the parts in question only 
by the dozens. They are sufficient, however, to show about 
all that can be expected to be shown by fossils. Upon the 
evidence of abundant and sufficient material at my command 1 
am compelled to dispute the correctness of the above state- 
ment m toto. That the depressions found by Mr. Bather m 
certain Cyathocrinidse, and figured by him (Crmoidea of Got- 
land, I, pi. vi, fig. 190, and text fig. 17, (2) p. 119, and else- 
where) lie at the angles of the plates, I have no doubi. But as 
to the structures which have been described by Wachsmuth 
and Springer as pores or fissures passing through the test in 
the Poteriocrinidge, I can state without fear of further con- 
tradiction that in the large number of cases where I have ob- 
served them, the rule is without exception that the position of 
the pores is the exact reverse of that stated by Mr. Bather. 
They are always "on the radial lines," i. e., in the middle 
of the sides of the hexagonal plates, and never at "the angles 
of the plates." This statement I will substantiate by evidence 
which I think will be satisfactory to all naturalists. 
The illustrations accompanying this paper are from draw- 
ings made with extreme care by an experienced artist, Mr. J. 
