Additional Notes on the Lilydale Limestone. 157 



In regard to the Cave Hill Limestone itself or rather it 

 contained fossils, before giving any additional notes on this 

 head, I have first to retract a statement I made in the paper 

 read here in July of last year as to the occurrence of a gasteropod 

 shell belonging to the genus " Stomatia," and which I called S. 

 antiqita, supposing it to be the oldest Stomatia on record. This 

 determination was an erroneous one, as it was founded upon 

 what has since turned out to be a very imperfect specimen of a 

 different shell, but which in its fragmentary form was so 

 strikingly like a Stomatia that I was quite "taken in" by the 

 appearance of it. However, I remarked at the time thut the 

 whorls were steeper in the sides and more flattened than Stomatias 

 usually are. A somewhat better specimen has convinced me that 

 the shell is not a Stomatia at all, but what it exactly is, it is 

 difficult to say at present, for even this specimen is by no means 

 perfect. It is possibly a very eccentric Trochus, eccentric of course 

 in the literal sense of the word in having the axis or columella very 

 remote from the centre, and besides this the whole shell is much 

 depressed for a Trochus. However, I have learnt caution, and will 

 endeavour to get a better specimen before committing myself to 

 anything beyond the assertion that it is not a Stomatia. 



EUGMPHALUS (OrIOSTOMA) NorTHI. 



I have much pleasure in being able to exhibit on the table this 

 evening a tolerably perfect specimen of Euomphalus Northi (or 

 according to Mr. Etheridge, Oriostoma Northi) with the operculum 

 that has been the subject of so much controversy in situ. The 

 controversy as to the operculum has been first as to the nature 

 of it, some taking it for a nummulite, and some for the lid of a 

 coral, others for the vertebra of a fish ; but I think there was a 

 general consensus of opinion amongst our Victorian geologists 

 from the first that it was the operculum of a gasteropod shell, the 

 only difference amongst us being as to what species of shell it 

 l^elonged to ; some thinking it was the operculum of Cyclonenia 

 others that it belonged to Euomphalus (or Oriostoma) Northi. 



The discovery of the specimen exhibited to-night must for ever 

 set at rest any further dispute both as to the nature of it and as to 

 the species to which it belongs. It is a veritable operculum, and 



