GEOLOGY OF THE WATKINS AND ELMIRA QUADRANGLES 9 



b o n a t a , Cyrtina hamiltonensis, Atrypa retic- 

 ularis, Leptostrophia mucronata, Palaeoneilo 

 constricta, P. cf . 1 a m e 1 1 a t a , Loxonema n o e , 

 Cladochonus sp., Manticoceras pattersoni and a small 

 un described Diaphorostoma occur. 



In an old quarry at 6io to 648 feet A. T., ^4 mile northwest of 

 Montour Falls and in the same horizon at the top of Montour Falls 

 and also by the roadside 10 rods farther north, the following species 

 occur : Manticoceras pattersoni, Orthoceras cf. 

 pacator, $4 y 1 i o 1 i n a fissurella, Palaeotrochus 

 praecursor , Buchiola retro^ striata, L 11 nil 1 i - 

 c a r d i u m hemicardioides, L. sp.?, Schizophoria 

 impressa, Spirifer mucronatus poster us, Lep- 

 tostrophia mucronata, Productella speciosa, 

 P. 1 a c h r y m o s a , Ambocoelia u m b o n a t a , C h o n- 

 etes lepidus. 



The thin seam in shaly sandstone at 590 feet A. T. exposed on the 

 road from Watkins to Burdett, Y\ niile north of Excelsior glen con- 

 tains : Leptostrophia mucronata, Ambocoelia 

 umbonata, Spirifer mesacostalis, Atrypa 

 reticularis, Productella sp., Orthis tioga? and a mass 

 of crinoid stems, and a similar layer at 580 feet A. T., % mile north- 

 west from Glenora contains Orthis impressa?, Chonetes 

 lepidus, Ambocoelia umbonata, Productella 

 cf. speciosa, and fragments of other brachiopods and small 

 lamellibranchs. It will be noted that these faunules are essentially 

 unlike, the lower beds containing species which typify the western 

 normal Portage or Naples fauna while the upper beds contain an 

 intermingling with some of these species of the brachiopods and 

 lamellibranchs of the more eastern or normal Ithaca fauna. 



Distinction between these two faunas will be less clearly marked 

 in this region which marks the boundary line of the geographic 

 provinces of the two. In regions farther west the brachiopod fauna 

 is virtually and almost wholly excluded from these rocks. In the 

 valley of Keuka lake the Ithaca fauna makes its appearance in the 

 upper part of the Cashaqua beds, and emphasizes the interlocking 



