74 'I he Irish Naturalist. April, 



ADVANCES IN IRISH MARINE ZOOLOGY. 



(third report). 



by r. f. scharff, ph.d., m.r.i. a. 

 Two previous articles on this subject have appeared in the 

 hish Naturalist.^ Since the last date the praiseworthy activity 

 of the zoologists attached to the Fisheries Branch of the 

 Irish Department of Agriculture and Technical Instruction 

 has resulted in the production of a large number of valuable 

 reports. Other reports, mainly on the material collected b)'' 

 the Department's cruises, have been contributed by some of 

 the staff of the Dublin Natural History Museum. A few of 

 the many papers dealing with Irish Marine Zoology have 

 already been alluded to in the Irish Naturalist ^ and are there- 

 fore omitted in this brief survey. 



In my last article I commented principally on the investi- 

 gations during the years 1 905-1 906. I now propose to deal 

 with the reports of the Fisheries Branch of the Department, 

 and other papers up to the end of last year.^ The various 

 notes and essays may be grouped with advantage under 

 different headings, as has been done on previous occasions. 



The reports on Eel fr}^ and Salmonidae, though not alto- 

 gether belonging to marine zoology, may as well be dealt with 

 here, as they are mostly concerned with these parti}' marine 

 and partl}^ freshwater fishes. 



General Biology. — Professor Milroy's paper ^ on the occa- 

 sional variations in the quantit}^ of glycogen present in Oysters 

 is not of apparent practical importance, but as ghxogen is a 

 chemical reserve material stored up in all animal tissues, the 

 determination of the quantity of this valuable asset in the 

 body of an oyster at any particular time will help us in esti- 

 mating the nutriment value of this important food suppl)' at 

 different periods. 



In order to extend our knowledge of the surface drift of 

 the Irish sea, Mr. Cunningham,^ at Professor Gregg Wilson's 

 suggestion, decided to carry out some very useful experiments 

 with artificial floats containing post-cards. Over 1,200 such 



* September, 1906, and July, 1907. 



2 [Including Fisheries, Inland, Set. Invest., 1907. ix. 1909]. 



' Mii.ROY, J. A. — Seasonal variations in the quantity of glycogen 

 present in samples of oysters. Fishtries, Ireland, Set. Invest., l^O"], iv. 

 [1909]. 



* Cunningham, C. xM.— Report on the drift of the Irish Sea. Fisheries, 

 Ireland, Sii. Invest-^ 1907, vii. [1909]. 



