T9I7- ScHARFF — Advances in Irish Marine Zoology. 109 



Mr. Farran supplies a further instalment of his Plaice- 

 marking experiments.^ 1 have already alluded to them in 

 my former article, and need not repeat the statements 

 contained therein. A smaller number of the marked fish 

 were recaptured than in previous years. 



Molluscs. — In my former article I also referred to Miss 

 Massy 's report^ on the Cuttle-fishes (Cephalopoda) of the 

 coasts of Ireland. The same author now makes some 

 necessary corrections to her list. The rare Teuthowenia 

 megalops has been added to the species occurring in the 

 Irish marine area. Another species, viz., Doraiopsis 

 vermicular is, has had to be withdrawn. 



Some people imagine that the age of an oyster is easily 

 ascertainable by counting the rings on its shell. If correct 

 this discover}^ would be of some commercial advantage to 

 oyster growers. But it is only a theory which had not 

 been seriousty tested until Miss Massy^ devoted herself 

 to it. Her conclusions are that it is not possible to tell 

 the age of an oyster with any degree of certainty by 

 counting the concentric rings on the shell. 



Crustaceans. — The tiny shrimp-like Crustaceans known 

 as " Schizopoda " are of considerable economic importance 

 since they form a large constituent of the food of fish. 

 Two reports on the species occurring on the Atlantic slope 

 were published some years ago. More material has ac- 

 cumulated since that time so as to enable Dr. Tattersall^ 

 to furnish us with another instalment of his researches 

 on these small Crustaceans. Eight species new to science 

 are now described from the deeper waters and several 

 forms which had not previously been known from the 

 Irish marine area. It is of interest to note that 

 Michthyops pavva and Hansenomysis fyllae, w^hich had 

 only been recorded from about 100 fathoms off the west 



^ Farran, G. P. — Plaice Marking Experiments on the East Coast of 

 Ireland in 1907. Fisheries, Ireland, Set. Invest., 1910, v. [191 1]. 



2 Massy, Anne L. — Further Records of the Cephalopoda Dibranchiata 

 of the Coasts of Ireland. Fisheries, Ireland, Sci. Invest., 1912, v. [1913] 



^ Massy, Anne L. — Notes on the Evidence of Age afforded by the 

 Growth-rings of Oyster Shells. Fisheries, Ireland, Sci. Invest., 19 13, 

 ii. [1914]- 



* Tattersall, W. M. — Schizopodous Crustacea from the North-east 

 Atlantic Slope. Second supplement. Fisheries, Ireland, Sci. Invest., 

 1910, ii. [1911], 



