152 



the suture, attenuated at the base; ornamented with about 18 

 angular costte, and about 20 equal and equi-distant broad flat 

 line, but narrower than the interspaces ; the whole surface with 

 conspicuous wrinkles of growth. 



Dimensions. — Length, 36; breadth, 21; length of aperture, 30. 

 Locality. — Calciferous sandstones. River Murray cliffs, near 

 Morgan. 



FAMILY CANCELLARID/E. 



Gexus Cancellaria. 

 synopsis of the species. 

 Shell umbilicated. 



Whorls lirate and costulated, deeply channelled at the suture; 



widely umbilicated. 1. C. calvulata. 



Whorls lirate, costa3 broad, widely channelled ; narrowly 



umbilicated. 2. C. laticostata. 



Whorls spirally ribbed, fenestrated by fine threads ; suture 



not channelled; widely umbilicated. 3. C. alveolata. 



Shell imperforate. 



Whorls variced. 



Suture channelled ; strongly lirate. 



Interspaces between s^^iral ribs finely striate. 



4. C. ejiidromiforinis. 

 Interspaces with a strong thread. 



5. C. exaltata. 

 Suture not channelled; finely lirate. 



6. C. varicifera. 

 Whorls not va^riced. 



Whorls squarely shouldered. 



Whorls more or less tessellated ; shell oval. 



Lirse on last whorl more than 1 ; posterior 

 area with a spiral thread. 



7. C. gradata. 

 Lirfe on last whorl about 10. 



8. C. iJtycliotropis. 

 Whorls strongly costated ; spire turreted. 



9. G. turriculata. 

 Whorls rounded. 



Shell oval. 



Cost?g well developed, roundly angular, ex- 

 tending to base of last whorl. 



10. C. Wannonensis. 

 Costai rounded, thick, on medial portion of 

 last whorl only. 11. C. semicostata. 



Lirate without costa?. 



12. C. modestina. 



