262 
GEOLOGY OF THE FOURTH DISTRICT. 
Some that could not be satisfactorily determined, and some others which have been figured in 
the Report of the Third District, are not here presented. 
As just before stated, the remains of Crustacea are rare in this group, which in this respect 
contrasts with the Hamilton, where, although there are few species, still they are abundantly 
distributed. The head of Calymene Bufo, and the tail of Dipleura Dekayi, have both been 
seen not far from Ithaca. 
The following illustration is the only perfect trilobite found in this group in the Fourth 
District: 
116. 
Calymene nupera, n. s.—General formeiongated, 
sides parallel; head three-lobed, middle lobe largest, 
and much extended anteriorly; articulations of the 
abdomen eleven, of the tail ? Eyes like those of C. 
Bufo , but less prominent. 
This fossil resembles the C. Icevis of Phillips, 
Palaeozoic Fossils, pi. 55, fig. 250. 
Locality —Chemung creek. 
Among the Aviculae, the first two figures are typical of that part of the group about Che¬ 
mung Narrows and several places in that county, and of the strata holding the same position 
in other places. The two next figures are of species marking the brownish sandstones at 
Painted-post, Jasper, and other localities holding the same position in the group. 
1 and 2. Avicula pecteuiformis. 3. Avicula longispina. 4. Avicula spinigera. 
