TERTIARY INVERTEBRATE FOSSILS. 



(CONTINUED.) 



MURICIDEA, Swains. 

 M. ( ? Phyllonotus] PAUCIVARICATA, n. s. 



PI. 14. Fig. 1. 



SHELL moderate in size, robust, fusiform, spire nearly as long 

 as the aperture ; whorls seven, subangulated, sloping above and 

 bearing eight or nine large longitudinal ribs which develop into 

 prominent nodes on the angle; on the body whorl these ribs dis 

 appear on the middle or towards the anterior part of the shell. 

 Aperture subovate above, narrowed anteriorly, canal slightly de 

 flected and often closed by a union of the two lips; labrum 

 thickened behind, acute on the margin, coarsely dentate inter 

 nally, and bearing a small compressed tooth a little below the 

 middle, inner lip incrusted by a smooth plate; umbilicus subper- 

 forate. Surface marked by two or three varices, acute on the 

 margins, never prominent, and not infrequently entirely obsolete ; 

 these varices are usually coincident with the longitudinal ribs ; 

 crossing them are from five to seven revolving ribs, between 

 each pair of which are six to eight smaller rounded ribs with 

 acute interspaces, giving the whole shell a closely costate surface; 

 in well-preserved specimens the revolving ribs are crossed by 

 small squamose plates, the remains of the lines of growth. 



Length 1.8 inch, width 1.05 inch, length of aperture 1.1 inch. 

 Locality : Post-Pliocene ; Santa Barbara, San Pedro, and San Diego. Not known 

 in a recent state. 



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