MARYLAND GEOLOGICAL SURVEY 459 



radius of the cortical sliell, basal diameter f the diameter of the medul- 

 lary shell. 



Occurrence.— CAhYEiir Formation. Plum Point. 



Collections.— Usivyland Geological Survey, Johns Hopkins University, 

 Kev. Edward Huber. 



Genus HEXASTYLUS Haeckel. 



Hexastylus simplex Vinassa. 



Plate CXXX, Fig. 23. 



HexciHtylm simplex Vinassa, 1900, Mem. d. R. Accad. d. Sci. d. Istit. d. Bologua, 

 ser. V, voL viii, p. 332, pL i, tig. 20. 



Description.— ' Sfera grande. molto spessa, scabrosa, a pori rotondi, 

 assai radi. Aculei muniti di una carena mediana, appuntiti. 



" Ha qualche somiglianza coll' H. marginatus Held. {Report on the 

 Badiolaria) figurato a tav. XXI, fig. 10, ma ha i pori assai meuo nuiner- 

 osi e gli aculei molto meno lunghi; 



"Diametro della sfera: mm. 0,15; lunghezza degli aculei: mm. 0,0(i." 



Vinassa, 1900. 



Occurrence.— Calvert Formation. Lyons Creek. 



Collections.— Maryland Geological Survey, Johns Hopkins University, 

 Eev. Edward Huber. 



Genus CENOSPH/ERA Ehienbeig. 



Cenospilera porosissima Vinassa. 



Plate CXXX, Figs. 34, 25. 



Cenosphcera porosUsima Vinassa, 1900, Mem. d. R. Accad. d. Sci. d. Istit. d. Bologna, 

 ser. V, voL viii, p. 329, pL i, tig. 3. 



Description.—'' Guscio assai grande, non molto spesso, scabroso, con 

 numerosi pori rotondi, equidistanti e fittissimi. 



"Diametro della sfera: mm. 0,125." Alnassa, 1900. 



Shell somewhat rough, pores regular and circular (or almost so), 

 two to four times as broad as the bars, six to eight on the quadrant. 



Occwrreiice.— Calvert Formation. Lyons Creek, Plum Point. 



Collections.— liavyland Geological Survey, Johns Hopkins University, 

 Rev. Edward Huber. 



