330 PALAEONTOLOGY OF NEW-YORK. 
The accompanying figures illustrate the interior of Ccelospiea and Zygospira : 
The Genus Uncites, which is characteristic of the European Devonian system, 
has not occurred among the collections made in the State of New-York, and so 
far as I know is not found in this country. Of the six genera of SpiriferidaE 
enumerated in the preceding pages, which do not occur in Mr. Davidson’s list, 
five of them are likewise known in the Silurian formations of this countiy. The 
Genus Merista, which is cited as occurring in the Devonian of Europe, is not 
known in our strata of the same age : and it is possible that the European forms 
of that geological period may present the same modifications as with us, and fall 
under the Genus Meeistella. Although not recognizing the Genus Retzia, which 
in Europe is characteristic of the Silurian and Devonian stages, we have in Trema- 
tospira and Rhynciiospira two allied genera. The other genera of this family 
enumerated in Mr. Davidson’s list are characteristic of more modern formations 
than those from which species are here described. 
* The disposition of the spirals in C<et.ospira is not very dissimilar from the same appendages in 
Roninckia, a Triassic genus of Brachiopoda. 
