TRILOBITES. 699 
Calymmene.] 
Clas ARTHROPODA. 
Subclass CRUSTACEA. 
Order PAPLOB EEA. 
Family CALYMMENIDA. 
Genus CALYMMENE, Brongniart, 1822. 
CALYMMENE CALLICEPHALA Green, 1832. 
Calymmene callicephala GREEN, 1832. Monogr. Trilobites N. Amer., p. 30, cast 2. 
Calymmene senaria MEEK, 1873. Paleontology of Ohio, vol. i, p. 173; pl. 14, figs. 14a f. . 
There are a number of small and quite perfect individuals from the Galena horizon 
which agree in all essential features with Ohio fossil. While following Mr. S. A. 
Miller and later writers in employing Green’s designation for this species, I feel that 
there is still a shadow over its accuracy, for the following reason: The specimen 
upon which the species was founded and which was very accurately reproduced in 
Green’s cast No. 2, was an extended individual, showing the peculiarly broad axis of 
f-- \ 
EES 
Fig. 2—Outline of cephalon of Calymmene callicephala Green. From the cast of the original. 
* 
the Cincinnati specimens, but having a very short glabella. The latter had been 
somewhat abraded, giving it apparently abnormal width, and I have not seen another 
example in which the width at the base is so great compared with the length of the 
glabella, and at the same time the anterior edge of the glabella so remote from the 
frontal extremity of the cephalon: To indicate this structure I have introduced an 
outline figure of the cephalon taken from this cast. It is stated in the original 
description that this specimen was labeled in the collection of the Philadelphia 
Museum as from Hampshire, Virginia; the author, at the same time speaking of 
others from the Miami river and near Cincinnati. There is, thus, no doubt of his 
intention to include the well known Hudson River form under this name: 
