EXPLANATION OF PLATE XIX. 



Fig. 1. Cyclonemaai(,stralis,Eth.&\. A nearly perfect spechnen seen from 

 the back. 



2. The same, front view. 



3. Cycloiiema lilydalemis, Eth. til. Siiglitly crushed example seen 

 from the back. 



4. Phanerotrema australis, Eth. til. A small individual, showing the 

 band, seen from the back. 



5. A full grown, although badly preserved example, seen from the 

 back. 



0. BcllcropJion cresswelli, Eth. fil. A broken specimen seen from the 

 front. 



7. The same fi'om the side, with the filled up umbilicus. 



8. The same from the posterior, exhibiting the band and sinus. 



[The tigures, from drawings by Mr. G. H. Barrow, of the Australian 

 Museum, are of the natural size.] 



