CANANDAIGUA AND NAPLES QUADRANGLES 



47 



phase of transition from the condition of the black sediments to 

 those of shallower and clearer water deposit, the fauna is also 

 mixed and transitional. It contains: 



Phacops rana Green rr 



Styliolina fissurella Hall c 



Pleurotomaria rugulata Hall. ... c 



Luimlicardium curtum Hall r 



Nuculites oblongatus Conrad c 



Chonetes setiger Hall c 



Spirifer mucronatus Conrad r 



^imbocoelia umVjonata Conrad.. .. c 



Llorhynchiis limitaris Vanu.Tem. c 



L. multicosta Hall c 



Canandaigua shale and limestone 



With these beds begins the profuse development of the cal- 

 careous Hamilton shales. Though the rocks of this stage are 

 treated as a unit on the map their faunas may be here con- 

 sidered in two divisions, that of (Ij the Centerfield limestones 

 or the calcareous befls at the base, (2) the upper division or the 

 Canandaigua shales. 



1 In the Centerfield limestones, best developed on Shaffer 



creek and underlying all the northern i>art of the village of 



Canandaigua, the following species have been noted: 



Cyrtolites mitella Hall 



Platyceras auriculatum Hall .... c 



F. symmetricum Hall c 



P. thetis Hall c 



Worms 



Arabellites r 



Oenonites r 



Eunicites r 



SpirorbLs angulatus Hall c 



Cornulites tribulis Hall r 



Crustaceans 



Phacops rana Green cc 



Dalmanites boothi Green cc 



D. bootbi var. calliteles Green. . . cc 



Proetus rowi Green cc 



P. macrocephalus Hall 

 Cyphaspis ornata Hall 

 C. ornata var. baccata Hall d 



Clarke 

 C. craspedota Hall & Clarke 

 Turrilepas devonica Clarke 

 T. squama Hall & Clarke 

 T. nitidula Hall & Clarke 

 T. foliata Hall d Clarke 

 T. tenera Hall & Clarke 

 Schizodiscus capsa Clarke 



Gastropods 

 Bellerophon pelops Hall 



F. subspinosum Hall 

 Pleurotomaria itys Hall 

 P. lucina Hall 



P. disjuncta Hall r 



Loxonema delphicola Hall 

 L. hamiltoniae Hall 



Lamellihranchs 



Mytilarca oviformis Conrad c 



Microdon bellistriatus Conrad 

 Conocardium crassifrons Conrad 

 Cypricardinia indenta Conrad... c 

 Actinopteria decussata Conrad. . c 

 Aviculopecten princeps Conrad. . c 



Lingula leana Hall r 



L. densa Hall 

 Crania crenistria Hall 



Craniella hamiltoniae Hall c 



Rhipidomella penelope Hall c 



BracJnoitods 

 It. vanuxemi Hall c 



