236 Cincinnati Society of Natural History. 
about one line apart from center to center, irregularly distributed over 
the surface, occupied by calices somewhat larger than the average. 
Margins ofcell apertures thin and sharp: no interstitial tubes observed. 
Calices polygonal and averaging about eight to ten in the space of one 
line. 
A microscopic section of the interior shows the tubes to be thin- 
walled throughout, of a somewhat duplex character, and very few, 
remote, indistinct tabule. A tangential section shows the angular 
calices and peculiar cruciform divisions in the tubes, which may be 
seen in some other species: no spiniform corallites noticed. A longi- 
tudinal section of a lateral projection shows the tubes springing from a 
medial axis, taking a sloping direction at first, then a wavy course to 
the surface, at nearly right angles. 
The specimen used for this description is seven inches long, over two 
inches in diameter at the thickest swelling, and one half to three fourths 
of an inch at the narrowest constriction. 
Found by Dr. T. D. Dyche, in company with the writer, near Leb- 
anon, Warren Co.,O. The only entire (apparently) specimen known 
to the writer, but many fragments of smaller examples have been 
collected at the same locality, and on the hill tops at Cincinnati. 
Named in honor of the discoverer. 
The interior structure of this species resembles M. sp. clavacoidea, 
James, but in other features it differs widely in habit of outward 
growth and otherwise. The central object around which the tubes 
crow and radiate of dychet is a crinoid column, whilst in sp. clava- 
coidea it is the tapering end of an Orthoceras, or some similar form. 
A question has been raised as to the central object in clavacoidea 
being an Orthoceras. The writer has specimens in his cabinet show- 
ing the Septa clearly, placing this feature of such specimens beyond 
doubt; in other specimens the organic structure of the Orthoceras has 
disappeared, and the space occupied by calcite or clay, or left as a 
vacant tube, but the outline remains, always. more or less sharply 
tapering, corresponding with Orthoceras. The evidence is positive in 
some cases, and the reasonable inference strong in others, that the 
central object is Orthoceras. 
