276 THK ATRYPIDAF, OF NEW SOFTH WALES. 



Figs. 3— 4. Ventral and front views of normal specimen from the same locality 



and Collection . 

 Fig. ."). A very large specimen (silicifiedi. showing, rather plainly, one spiral 



cone with some twenty coils and tongue-like, sinuation in front. 

 Reduced. Wellington. Coll. Minmg ,Museum. Sydney, X.S-W. 

 Figs. 6 — 7. Ventral views of two adult shells. Derrengullen Creek, near its 

 junction with Limestone Creek. Coll. Mitchell. 

 Atrypoidea aus/ralis Mitchell and Dun. 

 Figs. 8 — 9. Dorsal and ventral views, enlarged. Coll. Mining Museum Sydney. 



A/iypa ereilirostris Mitchell and Dun. 

 Figs. 10 — 11. Dorsal and ventral views of two specimens, slightly reduced. Cave 

 Flat. Coll. Mitchell. 



Atrypa desquamata Sowerby. 

 Figs. 12 — 13. Front and dorsal views of a specimen from Cave Flat, near the junc- 

 tion of the Gcodradigbee and Murrumbidgee Rivers. Coll. Mining 

 ' Museum. Sydney, N.S.W. 



Aiiypa inwginalis Dalm. 

 Figs. U — 16. \'entral. dorsal and front views of three nearly adult specimens. 

 Limestone Creek. Silverdale, near Bowning. Coll- Mitchell. 



Plate xvi. 



^■Itrypa Jiiarginalis Dalm. 



Figs. 1 — ,5. Photos of specimens of different stages of growth, slightly enlarged. 



Coll. Mitchell. 

 Fig. 6. A small specimen with concentric ornamentation, like A. Aspeia 



Schloth. Coll. Mitchell. 



Atrypoidea ans/ralis Mitchell and Dun. 

 Figs. 7 and 13. A sketch and photo, of a specimen from which the brachial is re- 

 moved and the spiral cones exposed. Fig. 13 (enlarged 2*. 

 Atrvpa diiii/i-ooiu'lisis Mitchell and Dun. 

 Figs. S — 11. Four different specimens, dorsal and ventral views. 

 Fig. 12. Same specimen as Fig. 9, enlarged (x 2). 



Atrypa pn/r/ira Mitchell and Dun. 

 Fig. 14. Dorsal view, sHghtly enlarged. 



Figs. 15 and 16. Ventral and dor.sal views of mature specimens (x 2'. Fig. 16 

 same as fig. 14. 'Limestone Creek. Coll. Mitchell. 

 Atrypa erec/irostris ilitchell and Dun. 

 Fig. 17. A voung specimen — shows the high, erect umbo, acutely pointed 



beak, steeply sloping umbonal ridges, and radial striae, (x 2.1 

 Fig. IS. An immature specimen in which the dorsal valve has been weathered 



away and exposed the spirals. The apex of the beak has been 

 weathered off. (x 2.1 Coll. Mitchell. 

 Atrypa reticularis Linn. 

 Figs. 19 and 20. Two specimens with the marginal fring s partly preserved. 



