ON THE MARINE ZOOLOGY OP THE IRISH SEA. 



527 



manner which though satisfactory to the evolutionist is aggravating to 

 the orderly systematist, the characters of the Styelinae and of the 

 Cynthinae. 



The Isle of Man is connected with Lancashire by a broad plateau 

 under 20 fathoms in depth (see chart and section, Plate IV.), to the north 

 and south of which prolongations of the western deeper water extend 

 inwards to the east. A considerable portion of our work has been done 

 in the broad southern extension which lies between Liverpool and the 

 Calf of Man (fig. 1), and gives depths of from 20 to 40 fathoms. 



Fig. 1 —Map of the L. M. B. C. District.' 



C, Calf of Man ; D, Douglas ; E, Port Erin ; H, Hilbre Island ; 

 P, Puffin Island ; R, Ramsey. 



In the shallower water around the coasts there is, of course, very 

 great difference in the physical conditions and in the fauna of different 

 regions ; for example, the sandbanks and flat expanses of mud off the 

 Lancashire coast are very different in every way from the more varied 

 ground off the rocky southern shore of the Isle of Man. But even the 

 seemingly uninteresting sandy wastes of Lancashire present many curious 

 facts and problems to the marine biologist. We find that on the estuarine 

 flats round Hilbre Island, as Lindstrom suspected to be the case on the 

 coast of Gothland some years ago, the very abundant Hydroiia ulvce lays 

 its eggs upon its neighbours' shells, probably as being the largest and 

 most stable objects among the shifting sand-grains around it. And it 

 may also be remarked that this supposed barren region is of immense 

 economic importance as a nursery for young food-fishes. 



Liverpool was naturally the headquarters of the Committee, but we 

 took advantage of the presence of the biological station at Port Erin, on 

 the south-west corner of the Isle of Man, to start our dredging expedi- 



' For the use of the figures illustrating this report we are indebted to the Liver- 

 pool Marine Biology Committee. 



