Clarke — The Naples Fauna. 



143 



PLATE I. 

 Maxticocekas Patteesoni, Hall (sp.). 



(See Plates II and IV.) 



Figure 1. The young shell up to the end of the ananeanic substage ; showing 

 the protoconch, the smooth surface of all nepionic substages and the 

 abrupt introduction of simple varices in the neanie stage, x 10. 



Figure 2. The young shell at 2i volutions. This is an entire shell in a 

 metaneanic condition, with the aperture and stomal callous preserved. 

 The varices are very strong at this stage and alternate with notable 

 regularity. The aperture is parallel to the varices which cross the 

 whorl without hyponomic curve, x 10. 



Figure 3. A complete shell at 21 volutions, with broad, direct varices reflected 

 at their tips; metaneanic substage. x 10. 



Figure 4. A still more progressed phase of this substage with a duplication 

 of the secondary varices. 2f volutions, x 10. 



Figure 5. A shell of about the same number of volutions but evincing a 

 more progressed condition in its finer and more numerous varices. 

 This feature is especially clear upon the last one-third volution. The 

 shell is entire, x 10. 



Figure «>. A somewhat oblique view of a shell in the same stage as the last, 

 showing a slight hyponomic recurvature of the varices on the final 

 whorl. The stomal callous is exposed for a half volution by the 

 breaking away of the shell to the first septum, which shows that the 

 body chamber at this growth stage is relatively short (compare 

 figs. 10 and 12). x 10. 



Figures 7, 8, 9. These are shells of 3— 3i volutions, which have entered the 

 paraneanic substage. They are all entire shells, except for a slight 

 breaking of the stoma, and all show the stomal callous. They evince 

 progress in growth, first in the fasciculation of the fine varices and 

 sequentially in their reduction to uniform size ; likewise in the 

 increasing hypononic curvature. From the close of this stage 

 onwai'd, the surface ornament becomes progressively reduced to a 

 series of uniformly fine lines with strong hyponomic curvature. 



