552 



PROCEEDINGS OF THE ALBUQUERQUE MEETING 



11. F. rectangitlus. 



12. F. tulieroicles cf. F. tiiherosus. 



13. Cladopora cf. cervicornis cf. C. cerviconiis. 



14. Syringopora cf. hisingeri cf. S. histngeri. 



15. Favosites concava. 



16. 7^. cf. maxhnus cf. Devonic specimens. 



Brachiopoda : . 



17. Stropheodonta vasculosa cf. S. patersoni mut. honamica. 



18. S. demissa JiomoJostriata cf. S. demissa var. 



19. (S. prepUcata cf. S. plicata. 



20. ProssereUa modestoides and mutation depressa cf. Devonic Spirifers of the Eifel. 



21. ProssereUa lucasi. 



22. P. suitransversa. 



23. (P. unilameJlosiis) cf. Devonic Spirifers of Europe. 



24. (P.planislnosus). 



Pelectpoda : 



25. Panenka canadensis cf. P. dicliotoma. 



26. Conocardium monroense cf. C. cuueus. 



Gastropoda : 



27. Troclionema ovoides. 



28. Hercynella cf. iJ. fastigiata Barr. 



TEiLOBiT.a: : 



29. Prcetus crasshnarginatus, P. crassimarginatus. 



This list of species shows that the Anderdon-Amherstburg fauna is most 

 nearly related to the Schoharie fauna of eastern New York, and that it prob- 

 ably represented the stock from which that fauna was derived. Coral reef 

 conditions existed in Michigan and Ontario at that period, the eastern exten- 

 sion of these conditions being first manifested in the waterlime deposits, and 

 later in the Akron, and finally in the Cobleskill. This latter marks the period 

 of reestablishment of connection with the Atlantic, and we find that this forma- 

 tion is especially characterized by an Atlantic fauna in its more eastern devel- 

 opment (Halysites, etcetera). The faunas mingled in the neighborhood of the 

 Schoharie region.* 



With the opening of the Atlantic connections the late Siluric Gastropod and 

 Cephalopod fauna entered this region and became characteristic of the succeed- 

 ing Manlius-Lucas deposits, while the typical Anderdon fauna soon disap- 

 peared. A comparison of the Anderdon and the Lucas fauna shows scarcely a 

 common species. In the Amherstburg, however, there is more or less of the 

 commingling of the two faunas. That the junction with the Atlantic was 

 effected while the Amherstburg beds were forming is shown by Siluric gastro- 

 pod and cephalopod elements in its fauna, and their absence from the Ander- 

 don fauna. The correlation of the Amherstburg and Cobleskill thus seems 

 evidenced. 



Considering the Anderdon fauna as a whole, we see a blending of types of 

 the Siluric with those of Devonic afiinities. Recognizing that this fauna is 

 interpolated between two Siluric faunae, we are forced to admit that here is an 

 example coming perilously near satisfying the demands of Barrande's theory 



^ A. W. Grabau : Bulletin of the New York State Museum, p. 1?>1. 



