Miscellaneous. 167 
single genus Cladocoryne, to which two species belong—namely 
Cladocoryne floccosa, Rotch, from the Mediterranean and Atlantic, 
and C. pelagica, Allm., which has hitherto been found only in the 
Atlantic. This second species, instead of being littoral and from 
the bottom, has, as its name indicates, a pelagic existence. M. 
Duplessis thinks that perhaps we ought to approximate to the latter 
another pelagic form described as a new genus by F. E. Schultze 
from specimens collected at Trieste upon Fuci.—Bibl. Univ., Arch. 
des Sci. Physiques et Nat., July 15, 1881, p. 98. 
Observations on the Structure of Dictyophyton and its Affinities 
with certain Sponges. By R. P. Wurrrrerp. 
In the Chemung group of New York and in the Waverley beds of 
Ohio and elsewhere there occurs a group of fossil bodies which haye 
been described under the name Dictyophyton, but the nature of which, 
I think, has not been properly understood. In the ‘Sixteenth Report 
on the State Cabinet of Natural History of New York,’ p. 84, in the 
remarks preceding the generic description, they are referred to the 
vegetable kingdom, with the opinion expressed ‘‘ that they are Algze 
of a peculiar form and mode of growth,” a reference which I think 
their nature does not warrant. 
If we examine the figures of the various species described, given 
on plates 3 to 5 a of the above-cited work, it will be seen that these 
bodies are more or less elongated tubes, straight or curved, cylin- 
drical or angular, nodose or annulated, and that they have been 
composed of a thin film or pellicle of network, made up of longitu- 
dinal and horizontal threads which cross each other at right angles, 
thereby cutting the surface of the fossil into rectangular spaces, 
' often with finer threads between the coarser ones. When the speci- 
mens, which are casts or impressions in sandstone, are caretully 
examined, it is found that these threads are not interwoven with 
each other like basket-work or like the fibres of cloth, nor do they 
unite with each other, as do vegetable substances; but one set 
appears to pass on the outside and the other on the inside of the 
body. The threads composing the network vary in strength, and 
are in regular sets in both directions, while the entire thickness of 
the film or substance of the body has been very inconsiderable. In 
one species, the only one in which the substance filling the space 
between the cast and the matrix has been observed, it appears to be 
not more than a twentieth of an inch in thickness, and is ochreous 
in character. ‘This peculiar net-like structure does not seem to be 
that of any known plant; nor does their nodose, annulated, cylin- 
drical, or often sharply longitudinally angular form, with nearly 
perfect corners, indicate a vegetable structure; moreover it is not 
a feature likely to be retained in a soft yielding vegetable body of 
such extreme delicacy and large size, while drifting about by the 
action of water, in becoming imbedded in the sand of a sea-bottom, 
