THE MOLLUSCA. 117 



truncata is occasionally found, with its long and curious 

 syphonal tube, alive and perfect. Several minute species may 

 be found by collecting the broken shell and sand from the 

 ripple marks and the slopes of banks, and examining a small 

 quantity at a time in a shallow dish of water, at home. 

 Dredging, unless at a very considerable distance out, is un- 

 productive; scarcely anything can be obtained but species 

 which may be commonly found on the shore. 



A collector may make a very pleasant excursion by taking 

 the train to Formby, crossing the sandhills to the shore, about 

 a mile distant, and walking back to Southport, in all from 

 eight to nine miles. A great many shells and other marine 

 curiosities may be found during the walk, and it avoids an 

 otherwise fatiguing return journey. 



The Mollusca which have been found on this coast up to 

 the present time, number 146 species. Of these 104 are marine, 

 7 of them being naked Mollusca (3 Nudibranchs and 4 

 Sepiadae); and 42 are land and fresh water shells. The 

 latter not being migratory to any extent, or not so subject to 

 causes of removal, are, of course, actually native, or indige- 

 nous to the district. Of the marine species, judging from a 

 lengthened period of observation, 43 may be considered 

 common, or native to the immediate coast ; 35 are occasional 

 visitors, living, say within a radius of fifty or sixty miles ; and 

 26 species occur so rarely, live at probably such a distance, 

 and require such conditions, as to oblige us to consider them 

 quite foreign to our shore. These 146 species have been 

 found in a space of seven or eight miles along the shore, and 

 extending about two miles inland. In so small a space, and 

 considering how barren non-observers might suppose the 



