Auriferous Districts of IVicklow. 85 



while noticing these, to collect into a uniform, and as far as 

 possible, complete list, all the scattered notices of the mineral 

 wealth of this particular district, which are to be found in 

 Mr Weaver s papers already referred to, and elsewhere. 



The principal point, however, with respect to the examina- 

 tion of these minerals, which appears to merit further and 

 more particular attention, is the fact of the existence of tin- 

 stone in such considerable quantity in these auriferous 

 streams : a fact which would seem to indicate the probable 

 existence somewhere in the surrounding district, of masses of 

 tne ore of this valuable metal of great extent, and possibly 

 forming the continuation, on this side of the Channel, of those 

 vast deposits which have contributed to furnish occupation 

 and support to the inhabitants of Cornwall for more than 

 two thousand years.* 



On the Natural History of the Naked- Eyed Medusae or Jelly 



Fishes. 



This interesting subject, already so extensively illustrated 

 by Professor Edward Forbes, in his beautiful workt is now 

 engaging the attention of Professor Agassiz, who has just 

 published " A Memoir on the Naked-eyed Medusae of the 

 shores of Massachusetts, in North America." Of that me- 

 moir no copy has hitherto reached this country, which we 

 regret, as we are informed it has brought to light much that 

 is new and important. — The species described are Sarsia 

 marabilis, Hippocrene super ciliar is, Tiaropsis diademata^ and 

 Staurophora laciniata. 



Professor Silliman, on announcing the publication of this 

 memoir, says, " Professor Agassiz, in the course of his me- 

 moir, makes some observations on the classifications of these 

 animals, and gives reasons for including all the naked-eyed 



* Transactions of the Geological Society of Dublin. 



t Monograph on the British Naked-eyed Medusae, by Edward Forbes, 

 F.R.S., &c., Professor of Botany in King's College, London, 1848. 



