NOTICE OF PALEONTOLOGY OF NEW YORK. 



195 



have a well-marked family of Brachiopoda which has existed from the 

 earliest palseozoic epoch, and has continued throughout the entire series 

 to its close. 



Under the Genus Pentamerella are placed P. arata ( = Pentamerus 

 arahts\ P . jyapilionensis ( = Pentamerus papilionensis) , P. micula (n. s.), P. 

 obsolescens (n. s.), and P. duhia (= Sjnrifer dubius, Hall, Thirteenth Report 

 on State Cabinet). 



The Genus Gypidula includes G. occidentcdis ( ^= Pentamerus occidentalism 

 Hall, Geol. Report of Iowa), and G. Iceviiiscula (n. s.). 



The term Amphygenia is proposed to include the original Pentamerus 

 elongatus of Vanuxem, which possesses characters imlike any other genus 

 of the pentameroid family ; the A. elongata, and a variety undidata. The 

 species formerly described as svhtrigonalis appears to be only a variety of 

 the A. ehngata. 



The Genus Renssel^ria is recognized with doubt, and a single species, 

 R.? johanni, is noticed from rocks of the age of the Upper Helderberg 

 group in Iowa. 



The Genus Terebratula is recognized in the following species : 



Terebratula lens, 

 T. sullivanti (n. s.), 



T. harmonia (ii. s.), 



T. rcemingeri, 



Terebratula elia (u. s.), 

 T. jucunda (h. s.), 



T. navicella (n. s.), 



T. sirmdalor (n. s.). 



It has been found necessary to preserve the generic term Cryptonella 

 for some of the species originally placed under that genus, as will be seen 

 from the following citation, pages 392 and 393 of the volume. 



GENUS CRYPTONELLA (Hall, 1861). 



Shells equilateral, inequi valve, elongate, oval or ovoid; valves 

 unequally convex, without median fold or sinus, or with this character 

 moderately developed and principally towards the base of the shell. 

 Ventral valve with beak extended or incurved, perforate; foramen ter- 

 minal, the lower side formed by two small triangular deltidial pieces, or, 

 in their absence, by the umbo of the opposite valve. Shell-structure 

 finely punctate. Surface smooth, or with concentric striae. Valves 

 articulating by teeth and sockets, the dental lamellae of the ventral 



external character, presenting certain modifications of the hinge-plate in the dorsal valve, vrhich 

 will require a distinct designation. 



