Tropidolepius Fauna at Canandaigua T.ake, N. \'. 177 



Row 3. Partial series of Orthotlwtes belltihts Clarke ; dorsal valves. X 2. 

 Rows 4 and 5. Series of Choietcs imici'matiis Hall ; ventral and dorsal valves. 

 X2. 



Row 6. Series of Cyrtina hamillonensis Hall ; dorsal valves. X 2. 



Pl.ATK VI. 

 Rows I and 2. Partial series of Spin'/er vtucronatus Conrad ; dorsal valves. 

 Row 3. Series of Chonetes coronatus Conrad ; ventral valves, exterior. 

 Row 4. The same ; dorsal valves, interior. 



Plate VII. 

 Rows I and 2. Series of Chonetes rolnistiis Raymond ; ventral and dorsal valves. 

 X 2. 



Rows 3 and 4. Series of Strophalosia truncata Hall ; dorsal and ventral valves. 



X2. 



Plate VIII. 

 Tropidoleptus caiinatus Conrad. 



Rows I and 2. Series of ventral valves. 

 Rows 3 and 4. Scries of dorsal valves. 



Note. — A bulletin of the New Vork State Museum (number 63), on " A Strati- 

 graphic and Paleontologic Map of the Canandaigua Lake and Naples Quadrangles" 

 has been issued since this article has been in the printer's hands. In it, the authors, 

 Dr. John M. Clarke and D. Dana Luther, refer to the so-called encrinal limestone 

 of the region as the Tichenor limestone and give the following section (in descending 

 order). 



9. Tully limestone about 3 feet. 



8. Moscow shale 125 feet. 



Intercalated in this, about fifty feet below the Tully and seventy- 

 five feet above the Tichenor, is the Menteth limestone, a foot in 

 thickness, in which the fossils are silicified. 



7. Tichenor limestone i foot. 



6. Canandaigua shale about 125 feet. 



5. Skeneateles shale 125 feet. 



4. Cardiff shale about 50 feet. 



3. Staflbrd limestone I foot (?) 



2. Marcellus shale about 50 feet. 



I. Onondaga limestone. 

 The writer furnished Dr. Clarke with a list of the fossils identified from the silici- 

 fied material here discussed and it is printed, with some additions by Dr. Clarke in 

 the above bulletin. The authors must, however, be in error in assigning the list to 

 the Menteth limestone alone, for I was assured by the late Dr. Beecher, whose skill 

 as a collector is universally recognized, that he had obtained the material from several 

 different layers through a range of some seventy-five feet above the encrinal limestone, 

 and during the process of etching I remember that he was particularly interested in 

 observing the relative value of the various layers as producers of fine fossils. 



The different blocks used differed greatly both in lithologic character and in fossil 

 contents, and must have been derived from various layers. 



