44 LIVERPOOL MARINE BIOLOGY COMMITTEE REPORT. 



The material from the above localities has been collected 

 and dried as usual, and the shells separated in the main by 

 the process of " floating ;" but several of the rarer species 

 have been obtained by the re-examination of such material as 

 refused to float at all. 



Dredgings have also been made at various points in the 

 Kiver Dee ; ofi" Khyl ; in Colwyn and Llandudno Bays, and 

 the Menai Straits ; and the material examined as usual ; but 

 not one example has been obtained in this manner which has 

 not also been found in shore gatherings. I do not mean to 

 infer by this statement that dredging is not likely to add to 

 the list ; on the contrary, I think it is from such sources that 

 any additions of importance are likelj to accrue. A glance 

 at the comparative lists of Dublin Bay, the material for which 

 was obtained chiefly by dredging, and Liverpool Bay will be 

 instructive in this respect. 



Surface dredgings have yielded absolutely nothing. The 

 estuary of the Dee teems at times with Diatoms and other 

 floating microzoa, and the tow net on such occasions, is soon 

 thickly coated with them. It is the same off Rhyl, Colwyn 

 and Llandudno ; but Foraminifera are conspicuous by their 

 absence. The experience of collectors in other seas proves 

 beyond doubt that certain species of Foraminifera are almost 

 exclusively pelagic when living ; but such is not the case with 

 our comparatively shallow water British forms. I have ob- 

 tained alive, and kept in bottles, and repeatedly examined 

 specimens of most of the types of Foraminifera enumerated 

 in the following list ; but these have invariably been got from 

 the mud at the bottom of shore pools of greater or less depth. 

 Under the influence of the sunlight, the Diatoms and other 

 Algae which grow in the mud at the bottom of such pools, 

 often rise to the surface in patches. These act as rafts, and 

 carry the Rhizopoda up with them. Once up, the outspread 

 pseudopodia enable even the largest and heaviest forms we 



