34 



NEW YORK STATE MUSEUM 



species (Climacograptus bicornis) and a few mutations or dis- 

 tinct derivatives viz, Leptograptus flaccidus heralded by L . 

 f 1 a c c i d u s mut. spinifer, Dicranograptus nicholsoni 

 with the prenuncial mutations diapason and parvangulus; D. 

 spinifer, Diplograptus foliaceus mut. yespertinus, 

 Lasiograptus bimucronatus mut. timid us. The common and 

 characteristic graptolites of the Utica shale are all new forms; the most 

 notable of these are : 



Corynoides curtus Lapworth G. ? eucharis {Hall) 



Glossograptus quadrimucronatus {Hall) Climacograptus typicalis Hall 



The last three cited graptolites the collector meets in almost even- 

 outcrop of typical Utica shale in both Canada and New York. Lepto- 

 graptus flaccidus, Dicranograptus nicholsoni and 

 Climacograptus putillus are very common in certain localities, 

 but absent in others and apparently of more restricted horizontal and vertical 

 distribution. Altogether, it is by no means to be assumed that the entire 

 above cited assemblage of graptolites is found in every locality ; on the con- 

 trary, the faunules of the localities are of so different aspects that the pres- 

 ence of subhorizons, only to be established by careful stratigraphic work, 

 can not be doubted. The following lists from some representative localities 

 in New York State will demonstrate this fact. 



The Utica shale of the Mohawk valley, which from the presence of the 

 type section in that valley is to be considered as representing the typical 

 development of the formation, contains the following graptolites : 

 Chaunograptus gemmatus nov. G. ? eucharis ( Hall) 



Dicranograptus nicholsoni Hopkinson Climacograptus typicalis Hall 



D. spinifer Ellcs & Wood C. putillus (Hall ) 



Corynoides curtus Lapworth Lasiograptus bimucronatus mut. timidus 



Diplograptus foliaceus mut. vespertinus nov. nov. 



Glossograptus quadrimucronatus {Hall) 



There are again distinct differences in the distribution of these forms 

 recognizable in the Mohawk valley. D i c r a n o g r a p t u s n i c h o 1 s o n i 

 and D. spinifer have only been found in one locality, i. e. Fort 



