97 



REPORT ON THE INVESTIGATIONS CARRIED 

 ON DURING 1919 IN CONNECTION WITH THE 

 LANCASHIRE SEA-FISHERIES LABORATORY AT THE 

 UNIVERSITY OF LIVERPOOL, AND THE SEA-FISH 

 HATCHERY AT PIEL, NEAR BARROW. 



EDITED BY 



Professor W. A. HERDMAN, C.B.E., F.R.S., 



Honorary Director of the Scientific Work. 



(With Text-Figures.) 



Contents. page 



1. Introduction. By W. A. Herdman ... ... ... ... 97 



2. A Mid-Winter Invasion of Noctiluca and Ctenophora. By A. Scott 102 



3. Food of Port Erin Mackerel in 1919. By A. Scott 107 



4. On the Dietetic Values of Herrings and other Fishes. 



By J. Johnstone ... ... ... ... ... ... ... 112 



5. On Certain Parasites, Diseases and Abnormal Conditions of Fishes. 



By J. Johnstone ... ... ... ... ... ... ... 120 



6. A Contribution to the Ecology of some Cockle Beds. 



ByC. L.Walton 130 



7. On the Shell of Cardium edule. By C. L. Walton 143 



8. On Periodicity in the Abundance of Plaice off the Mersey Estuary. 



ByR. J. Daniel ... 147 



9. On the Results of a Drift Bottle Experiment made in 1913. 



ByR. J. Daniel 168 



10. Intensive Study of the Plankton in the Irish Sea. Part XII. 



By W. A. Herdman, A. Scott, and H. Mabel Lewis 17f> 



INTRODUCTION. 



Last year in the Editorial Introduction to the Report 

 it was pointed out that I was writing for the last time as 

 Professor of Zoology in the University of Liverpool ; and 

 now, as Professor of Oceanography for one year, I have the 

 honour to submit to the Committee the last Annual Report 

 on the Scientific Fisheries work in which I can appear as 

 editor or compiler. Dr. James Johnstone succeeds me as 

 Professor of Oceanography on October 1st, 1920, and into 

 his capable hands passes the production of these reports from 

 that time onwards. 



