466 PROCEEDINGS OF THE ACADEMY OF [July, 



two in number on the whorls of the spire and four on the medial 

 portion of the ultima, separated by shallow channels of approximately 

 the same width as the fillets; shoulder sloping at an angle of about 

 45°, very feebly convex; sculpture with retractive undulations 

 corresponding in number and proportion to the axials with an obscure 

 secondary liration and revolving a little behind the periphery; base 

 of body and pillar threaded with flattened spirals which become 

 increasingly narrow anteriorly; suture quite deeply channeled, 

 undulated in harmony with the preceding volution, body whorl 

 constricted rather abruptly into a broad pillar; aperture pyriform. 

 produced anteriorly into a narrow canal; outer lip broadly expanded; 

 crenulated at the margin and feebly cordate within, the cords 

 restricted to the margin and corresponding in position with the 

 interspiral areas; inner lip broadly concave, non-plicate; parietal 

 wall heavily glazed and bearing an obscure tooth directly in front 

 of the posterior commissure; edge of pillar flattened at the entrace 

 of the canal simulating a fold, canal sharply recurved, moderately 

 long and narrow with parallel proximate margins; umbilicus closed 

 by the reflected inner wall of the aperture but indicated by a depres- 

 sion between the callus and the anterior fasciole. 



Dimensions. — Altitude, 44 mm.; length of aperture and canal, 

 28 mm.; maximum diameter, 32.4 mm.; spiral angle, 70°. 



This elegant species is represented in the Coon Creek collection 

 by perfectly preserved specimens. The species is characterized by 

 the obliquely shouldered whorls, the prominent subnodose intersec- 

 tions of the banded spirals and the undulatory axials, further by the 

 low spiral angle and outline of cross-section of body. 



Occurrence. — Ripley Formation: Dave Weeks Place, on Coon 

 Creek, McNairy County, Tennessee. 



Family EUOMPHALlD^l. 

 Genus HIPPOCAMPOIDES gen. nov. 



Etymology: i-7tuy.ap.7:o$ ) sea-horse; eldo? y shape. 



Type: Hippocampoides serratus sp. nov. 



Shell rather small, flattened or feeble apically; widely and deeply 

 umbilicate; protoconch minute, planarboid, paucispiral; whorls of 

 conch relatively few, increasing rapidly both in diameter and altitude 

 toward the aperture; external surface usually smooth; peripheral 

 margin acutely angulated, often sharply serrate; aperture holo- 

 stomous, umbilicus funicular, the outer margin acute, conspicuously 

 produced anteriorly. 



