18 



Report of the State Geologist. 



Syringothyris Missouri 

 Athyris densa. 

 Seminula Rogersi. 

 S. Dawsoni. 

 T rynifer criticus. 

 Rhyrtchospira scansa, 

 Trematospira Te7tnesseensis. 

 Meristella WalcoUi. 

 Merista Tennesseensis. 

 Clintonella vagahunda. 

 Zygospira putilla. 

 Atrypina Cli7itoni. 

 Glassia Romingeri, 

 Gamarophoria rhomhoidalis. 

 Parastrophia divergens. 

 JP. Greenei. 

 P. multiplicata, 

 P. latiphcata. 

 Liorhyuchus robustus. 

 L. Lesleyi. 



Gonchidium exponens. 



G. scoparium. 



G. ohsoletum. 



G. Greenei. 



G. crassiplica, 



G. Georgice. 



Pentamerus ohlongus^ var. Maquo- 



keta. 

 P. ohlongus, var. subrectus. 

 Gapellinia mira. 

 Barrandella Areyi. 

 Gypidula tiomingeri. 

 Sieberella Roemeri. 

 Rensselaer ia Gayuga. 

 H. ovatum. 

 Oriskania namcella. 

 Selenella gracilis. 

 Gryptonella sub lliptica. 

 Beechtria Pavidsoni. 

 Pielasma obovatum. 



Bryozoa. 



Mr. George B. Simpson has communicated a memoir contain- 

 ing descriptions of the genera of the IS'orth American Palaeozoic 

 Bryozoa, with an introducti-m upon the structure of living spe- 

 cies, intended as a hand-book for the use of students, illustrated 

 by 26 plates and numerous text illustrations. 



The first portion of this work is devoted to the recent Bryozoa 

 and contains the history of observations upon these organisms 

 from 1599 to the present time, followed by a bibliography in 

 which 135 titles are cited, and an illustrated detailed account 

 of the anatomy under the headings, 1, the Cell; 2, Opercula; 

 3, Avicularia and Yibracula ; 4, the Animal ; 5, Alimentary 

 Canal ; 6, Lophophore and Tentacles ; 7, Perigastric space ; s, 

 Muscular system ; 9, Nervous system ; 10, Keproductive organs ; 

 11, Embryology; 12, Statoblasts. 



The second part is devoted to the fossil forms from the Palaeo- 

 zoic rocks, and contains a scheme of classification, the bibliogra- 

 phy of the Palaeozoic species of America, a list of all the genera 

 and species described, with references to authorship and the geo- 



