159 



13. Peristernia interlineata, si)ec. nov. Plate vi., fig. 1. 



Shell ovately fusiform, with a moderately high subgradated 

 spire, ending in a blunt apex of one a half subglobose whorls, 

 the tip depressed. Whorls below the apex four, convex, equally 

 contracted at both sutures, spirally ridged. 



Eidges angular, acute, three or four of which on the median 

 portion of the spire whorls forming keels ; the broad concave 

 furrows with a thread, crossed by straight distant striae. On 

 the body whorl the ridges are more serrately cut by the trans- 

 verse striae than those are on the spire. 



Aperture oval; outer lip thin, closely and strongly lirate 

 within ; peristome continuous ; inner lip with a thin erect 

 margin, a strong oblique anterior plait, and a few denticles. 

 Canal long, slender, twisted to the left and reverted. 



Length, 23 ; breadth, 11 ; length of aperture 8*5, of canal 7. 



LocalUy. — Lower beds at Muddy Creek. 



E-elated to P. succincta by its ornament, but it is elongated 

 and has a long tapering canal. 



14. Peristernia subundulosa, spec. nov. Plate viii., fig. 12. 



Shell similar to P. interlineata but the whorls are regularly 

 convex ; the spiral lirse flatly rounded, no intersticial thread in 

 the wider interspaces (about ten on the penultimate whorl) ; 

 lirae undulose by reason of the obscure, broad, transverse 

 wrinklings. There are two small plaits and a tooth on the 

 columella, in addition to the prominent fold at the junction 

 with the canal. 



Length, 23'5 ; breadth, 11 ; length of aperture 9, of canal 7. 



Locality. — Lower beds at Muddy Creek. 



GrENUS TtJDICULA. 



STJ^OPSTS OF SPECIES. 



Periphery truncated and costated. 1. T. costata. 



rounded, undulose. 2. T. turhinata. 



angulated, plain. 8. T. angulata. 



It is noteworthy that the above-named fossils conform more 

 with the type of the genus (T. sjyirillus) than does any of the 

 living species associated therewith ; the recent species, which 

 number five, are confined to the Indo-Australian region. Each 

 of the fossil species has very distinctive characters as com- 

 pared with T. spirillus. 



1. Tudicula costata, spec. nov. Plates., fig. 9. 



Shell globosely conical, with a very short conical spire ; apex 



mamillate of two whorls, erect, and a little lopsided. Surface 



ornamented with numerous spiral threads alternately large 



and small and transverse striae. Last whorl truncated at the 



