94 Upper Cretaceous Fauna from Tennessee [292 



single small individual which has been assigned to the genus 

 Columbellina, a group not previously reported from the Cre- 

 taceous of North America. One species of the genus Pugnel- 

 lus of the Strombidae is very common in the Coon Creek beds. 

 A species of Rimella of the same family is represented by one 

 specimen. The family Aporrhaidae is prolific, its two gen- 

 era Aporrhais and Anchura include probably nine species. 



In the suborder Streptodonta the families Scalidae, Ceri- 

 thiidae, Trichotropidae, Vermetidae, and Turritellidae are 

 each represented by a single genus. In the genus Turritella 

 there are probably 8 species. Both Lunatia and Gyrodes of 

 the Naticidae are common. The individuals of one species 

 of Lunatia are probably more abundant than any other gas- 

 tropod species. The family Capulidae is represented by 

 small, fragile individuals of a single species of the genus 

 Thylacus which was described from Owl Creek by Conrad in 

 I860. 24 The individuals of this species are small and very 

 fragile, yet they are abundant and perfectly preserved in 

 their natural habitat. They occur in place fitting snugly to 

 the columellar walls in the body cavities of larger gastropods. 

 They have the internal muscular impression produced and 

 leaving the wall of the shell at the anterior extremities, and 

 lack the calcareous foot-plate characteristic of the genus 

 Hipponix of this family. The family Littoriniidae is repre- 

 sented by the genus Littorina which is common in the Ter- 

 tiary and Eecent of the East Coast and Gulf regions, but up 

 to the present has not been reported from the Cretaceous of 

 these regions. f - 



The genus Leiostraca of the family Eulimidae and order 

 Aspidobranchiata is represented by abundant but often poor- 

 ly preserved specimens, due to the fragility of the shell. 

 The family Euomphalidae which is variously represented in 

 both the Paleozoic and Mesozoic, includes a new genus Hip- 

 pocampoides. This is a much depressed form with a pro- 



24 Conrad, T. A., Jour. Acad. Nat. Sci., Philadelphia, 1860, vol. iv, 

 2d ser., p. 290, pi. 46, fig. 22. 



