Weller — Ktnderhook Faunal Studies. 443 



beak of its pedicle valve and the well developed pseudodelti- 

 diuni, it differs notably from the terebratuloid shells of the 

 genus Didasma commonly present in the Mississippian faunas, 

 and it has much more the aspect of certain Devonian shells. 

 In the characters of the beak as well as in the length of the 

 brachidium, the shells agree with the definition of the genus 

 Eunella. The complete form of the brachidium has not 

 been determined in the Glen Park specimens, only the pri- 

 mary lamellae having been observed, but these determine the 

 length of the loop, and in the genus ^wwe/Za the recurved con- 

 necting lamella is always feebly developed and has usually 

 been destroyed. 



The species may be compared with E. lincklaeni Hall, from 

 the eastern Hamilton fauna, but the shell is smaller and much 

 more compressed and may be easily distinguished by its con- 

 spicuous median flattened region on each valve. 



Crtptonella? sp. undet. 



Several specimens of a terebratuloid shell have been ob- 

 served, the larger of which are several times the size of mem- 

 bers of the species last described. These specimens are all sep- 

 arated valves, but they indicate species not only larger but also 

 much thicker than the last. The beak of the pedicle valve is 

 erect so that the pseudodeltidium is well developed, and the 

 foramen rather large. The aspect of the shell is much more 

 that of the Devonian species referred to the genus Crypto- 

 nella or some of its near allies, than to the Mississippian 

 member* of the genus Dielasma^ with their more strongly in- 

 curved beaks. The form of the brachidium has not been 

 observed, so that the true generic position of the shells can- 

 not be certainly determined. 



AtRYPA 8PIN08A Hall. 



Plate 1, Jiff. 17. 



A single small specimen of this species has been detected in 

 the Glen Park fauna. Its length and breadth are equal, both 

 being 7 mm., and its thickness is 3 mm. Its markings consist 

 of rather coarse, radiating plications with lamellose, concen- 

 tric lines of growth, which are more produced upon the tops 



