32 NEW YORK STATE MUSEUM 
represented the carapace of Eurypterus as evenly rounded with the excep- 
tion of the frontal elevated areas. 
The usual waterlime material does not give any evidence of the original 
form of the carapace of Eurypterus, the integument having been com- 
pletely flattened out in the fine mud. A sandy dolomite bed of the Bertie 
waterlime at Morganville, Genesee co., has however furnished a few speci- 
mens of Eurypterus remipes that are uncompressed. These 
(pl. .6, fig. 6] have glabellalike posterior median ridges well defined 
by two subparallel furrows deepest half way between the posterior 
Figure 5 Transverse section through the head of Limulus 
ht, heart; liv, liver; es, entosternon; end, endognathite. (From Packard) 
margin and the ocellar tubercle, which, by the way, the glabella does not 
quite reach. They also show a crest extending from the lateral eyes to 
the posterior margin and separating the elevated apical area from the 
steeply outward sloping lateral areas. This sculpturing is so remarkably 
like that of Limulus that we have no doubt it represents a general feature 
of the eurypterids. The dorsal furrows bounding the glabella correspond 
to entapophyses, serving for the attachment of muscles. The appended 
sections of Limulus [text fig. 5, 6] show the relation of the glabella 
to the position and extension of the heart and the relation of the 
glabellar furrows to the muscles holding in place an internal cartilaginous 
