144 THE DEVONIAN OF MISSOURI. 



the middle of the front, abruptly pointed at the beak; cardinal slopes concave; sides 

 rounded to the mesial fold and sinus. 



Ventral valve flabelliform, depressed-convex, rarely a little gibbous on the umbo, 

 flattened and depressed in the middle towards the front; the sinus becoming perceptible 

 about the middle of the length; sides nearly flat; apex abruptly acute, and more or 

 less incurved according to age. 



Dorsal valve gibbous, regularly arching transversely; the mesial fold becoming 

 conspicuous only towards the front; in young shells only moderately convex. 



Surface marked by twenty to twenty-two or twenty-four plications (fourteen 

 or fifteen in the young shells), those towards the cardinal margin less elevated; about 

 four to six mark the sinus and fold. In old shells, the plications are grooved towards 

 the front; and those of the sides of the dorsal valve are very abruptly bent towards 

 the ventral valve, with a shorter and wider groove, and all deeply bifid for the reception 

 of the opposite plication. The shell is concentrically marked by fine thread-like ele- 

 vated striae, which are more conspicuous and strongly undulating towards the front 

 of the shell, their remains being often preserved in the casts. 



Length and width, in full-grown shells, as seven to eight." 



Remarks — One specimen of the species from Ste. Genevieve County is in the 

 collection of the University of Missouri. It was sent in by a boy who lives in the valley 

 of Little Saline Creek. With it were several Nucleocrinus verneuili (Troost). The speci- 

 men probably came from the Grand Tower limestone. It is well preserved save that 

 the beaks of both valves are missing. 



Camarotoechia welleri n. sp. 

 Plate 34, figures 3, 4, 5 and 6 



Description — Shell small, longer than wide, length 7J^ mm., width 7 mm. 



Pedicle valve regularly convex from front to beak. Beak pointed, only slightly 

 incurved. Sinus of moderate depth, originating behind the middle of the shell and 

 projecting in front of the rest of the shell. Three rounded plications in the sinus. One 

 or two large plications on either side of the sinus, the larger bounding the sinus. Total 

 number of plications, about 7. 



Brachial valve nearly straight from front to back. The fold originates near the beak 

 and becomes prominent near the front. Two plications on the back half of the fold 

 which bifurcate to form four at the front margin. One or two large rounded plications 

 on either side of the fold. Other incipient plications make the margin irregular. 



The species is based on one specimen which differs markedly from any other species 

 known to the writers. 



Occurrence — Grand Tower limestone, Little Saline Creek, Ste. Genevieve County. 



Superfamily Terebratulacea 



Family Terebratulidae 

 Genus Eunella Hall and Clarke 



Eunella lincklaeni (Hall) 



Description and synonomy on page 93 



Figured on plate 20 



Remarks — Only a few poor specimens of this species have been collected. They 

 agree in every respect with specimens from the Mineola of Montgomery and Ralls Coun- 

 ties. 



Occurrence — St. Laurent limestone of Little Saline Creek, Ste. Genevieve County. 



