228 PALEONTOLOGY OP NEW JERSEY. 



in the Mineral Conchology, being less elevated above and less convex 

 below, and never umbilicated; while that one is only covered at the um- 

 bilicus when very old. Sowerby also distinctly states that that shell never 

 attaches foreign substances to its surface, while this one is quite covered, 

 and principally by small stones, even where shells appear to have been 

 abundant. In this respect it differs quite notably from Tliorus leprosus 

 Morton, as that one principally used shells, and those frequently of large 

 size enough to quite disfigure the casts, while those of this species are 

 quite regular in outline. 



Formation and locality: In the upper layer of the Upper Green Marls, 

 common at Shark River, New Jersey. I have also seen it from Farm- 

 ingdale. 



SOLARIID^. 



Genus ARCHITEOTONICA Bolton. 

 Akchitectonica annosa. 



Plate XXXIV, Figs. 23-27. 



Onustus annosus Conrad: Am. Jour. Conch., vol. 5, p. 42, PI. i. Fig. 4. 

 Comp. A. {Solarium) elaborata Con.: Tert. Foss. N. A., PL xvii. Fig. 4. 



Mr. Conrad figures in the Am. Jour. Conch., loc. cit., under the name 

 Onustus annosus a specimen which I judge to be the cast of a species of 

 Architectonica, which is rather common in the Shark River Eocene Marls. 

 The specimens which I have figured under the above name were at one 

 time studied by him, and I presume the figure in the Journal was drawn 

 from one of them. External casts, or imprints of the exterior, however, 

 show quite distinctly that the shells were of the nature of the genus Arch- 

 itectonica Boltou^ Solarium Lamarck. Mr. Conrad's description of his 

 Onustus annosus is as follows: "Rather elevated; volutions five, rounded, 

 slightly channeled at top, and sculptured with revolving lines, which are 

 obliquely crossed by others, giving the cast a rugoso-tuberculated aspect; 

 lines on the last volutions five or six in number; periphery acute." 



There is nothing embraced in this description that might not apply 

 equally well to a species of either of these genera, unless it be the feature of 



