MARYLAND GEOLOGICAL SURVEY 251 



Family AMALTHEID/E. 



Genus AMALTHF.A Schumacher. 



Amalthea marylaxdica n. sp. 



Plate LIX, Figs. 6a, Gb, 6c, Gel. 



Description. — Shell small, irregular in shape; apex very posteriorly 

 situated (overhanging the margin), elevated, arched, and dextrally 

 twisted ; surface with irregular lines of growth, and numerous, closely-set, 

 alternating, granulated ribs ; base irregular ; margin smooth. 



Height, 3 mm. ; length, 9 mm. ; width, 7.5 mm. 



Occurrence.— QjiovTX^K Formation. Greensl^oro, Jones ^Vha^f. 



Collection. — Maryland Geological Survey. 



Family XENOPHORID/E. 



Genus XENOPHORA Fischer. 



Xenophora conchyliophora (Born). 



Plate LIX, Figs. 7a, 7b, 7c. 



Trochus coHchijliophonts Born, 1780, Testacea Musei Ciesarei Vindobonensis, p. 333, 



pi. xii, figs. 31, 33. 

 Xenophora hnmilu Dall, 1890, Trans. Wagner Free Inst. Sci., vol. iii, pt. i, p. 183 



pi. iv, figs. 10, 10a. (Not of Conrad.) 

 Xenophora conchyHophora Dall, 1893, Trans. Wagner Free Inst. Sci., vol. iii, pt. ii 



p. 360. ' ' ' 



Description. — "Testa convexo-conica, tenuis, sub-pellucida, testis 

 Zoophytorum & Testaceorum adglutinatis onerati; Anfractibus declivis, 

 imbricati, plicato-rugosi ; Apertura compressa, subquadrangularis ; Lab- 

 rum integerrimum, falcatum ; Labium horizontale, reflexum, imperfora- 

 tum; Color albus, radiis obliquis curvatis luteis." Born, 1780. 



This species has survived without essential change from the Cretaceous 

 to the Eecent. 



Height, unknown ; diameter, 43 mm. 



Occurrence. — Choptank Formation. Governor Eun (lower bed). 

 Calvert Formation. Plum Point. 



C'o/Zeff(:ons.— Maryland Geological Survey, Johns Hopkins University, 

 U. S. Xational Museum. 



