260 



Report of the State Geologist. 



Genus Cypricardinia, Hall. 



66. Cypricardinia indenta, Conrad. 



1885, Hall, Pal. N. Y., vol. 5, pt. 1, p. 485, pi. 79, 96. 



This is one of the most abundant species of lamellibranchs in the upper 

 part of the Hamilton shales. It is extremely abundant in the upper part of 

 the shale, but rare below. Two specimens were found between two and three 

 feet below the Encrinal limestone, but none between this and the Trilobite 

 beds. Below the latter it is not an uncommon form down to the Nautilus 

 bed. The specimens are usually well preserved, in many instances retaining 

 the shell entire, and showing the two sets of striae. The specimens on the 

 whole are smaller than the average as given by Professor Hall. Five measure- 

 ments resulted as follows: length, 6, 5, 7, 12, 12.5, 17.5 mm.; height, 4, 4.2, 

 6.8, 6, 10 mm. It will thus be seen that there is some variation in the proportion 

 of length to height. A single specimen, probably from the lower two feet of 

 the Moscow shales, belongs here, but the exact position of the fossil is some- 

 what doubtful. It is the only one found in the Moscow shales. 



Genus Modiella, Hall. 



67. Modiella pygm^ea, Conrad. 

 1885, Hall, Pal. N". Y., vol. 5, pt. 1, p. 514, pi. 76. 

 A single small left valve from Idlewood ravine twenty-five feet below 

 the Encrinal limestone, is of this species. The specimen is denuded of the 

 test, but the radiating striae are faintly indicated on the cast. The form and 

 proportions are those of the typical individuals from the center of the state. 

 A few small specimens, chiefly casts from the Strophalosia bed, are referred to 

 this species. 



Genus Tellinopsis, Hall. 



68. Tellinopsis subemarginata, Conrad. 



1885, Hall, Pal. N. Y., vol. 5, pt. 1. p. 464, pi. 76. 



Of this well marked species a single specimen was found in the Strophalosia 

 bed. The test is dissolved and no radii are shown, but the identity of the 

 specimen is beyond doubt. 



