Ulrich on Correlation of the Lower Sihcrian. 309 
Cyclo^hycus laterale^ Batostonia erraticzim^ Aspidopora P caly- 
cula^ Afnbonychia n. sp^ and Tetradium Jibratuni (rare.) 
Two or three feet below the nodule layer there is a strongly 
undulated limestone, 3 to 10 inches thick, containing Tellincmya 
alta^ in great abundance. From this la3^er to low water mark 
(about 18 feet) the section consists mainly of hard and softer 
shales, grayish or drab colored when weathered, and several 
courses of impure limestone. Aside from rather numerous frag- 
ments oi Asaphus fossils are comparatively rare. 
In going up the river to the mouth of the Licking the slight 
rise in the strata brings up about 4 feet more of the series. 
These consist of a number of courses of subcrystalline dark or 
grey limestone, four to six inches thick, separated by nearly the 
same amount of shales. The upper layer of limestone gener- 
ally contains many good examples of jSIodlolopsis chicin7iatien- 
sis, while the lower ones are full of ostracoda, and hold also a 
considerable number of Asaphus fragments. The shale bands 
contain Pterinea insueia^ Litigtda cobourgeiisis and, one band 
in particular, great numbers of Leptobolus lepis. This same 
horizon is exposed several miles up the Licking river. Here 
they furnished also species of conodonts referable to Deprano- 
dus. 
Several feet of shales that are supposed to rej^resent the j^or- 
tion of the section immediately below that mentioned in the 
preceding paragraph are exposed under the bank of the river in 
the first ward of Cincinnati. They can only be reached when 
the water is very low, but as the river rarely fails to drop to 
the desired level at least once during the summer, this draw- 
back is not very serious. 
Several fossils occur in these shales that are not found else- 
where in the immediate vicinity of Cincinnati. Triarthrus 
becki which they contain in abundance, is probably their most 
important fossil ; but none the less interesting are certain grap- 
tolites which have been found in ttem. These and other fossils 
that add interest to the beds are: Graptollthus gracilis, Dic- 
ranograptus rafnosus, Diplograptiis spinuhsus, Aspidopora 
areolata, A P newberryi, Leptcena pUcatella, Lingula ricini- 
formis^Lcpcrditia radiata^Merocrinus curtus,a7idStenocrinus ? 
geniculatus. A colony of Palccastcr Jinci, comprising more 
