268 THE LIFE OF PHILIP HENRY GOSSE. 



" — their powers of floatation — whether earth sticks to 

 "birds' feet or base of beak, and I am experimenting 

 "whether small seeds are ever enclosed in such earth, 

 " etc. Can you remember any facts ? But of all cases 

 "whatever, the means of transport (and such I must 

 " think exist) of land mollusca utterly puzzle me most. 

 " I should be very grateful for any light." 



"Moor Park, Farnham, Surrey, April 27, 1857. 

 " My dear Sir, 



" I have thought that perhaps in course of the 

 " summer you would have an opportunity, and would be 

 " so very kind as to try a little experiment for me. I 

 " think I can tell best what I want by telling what I 

 " have done. The wide distribution of some species of 

 " fresh- water molluscs has long been a great perplexity 

 "to me ; I have just lately hatched a lot, and it occurred 

 "to me that when first born they might perhaps have 

 " not acquired phytophagous habits, and might perhaps 

 " like nibbling at a duck's foot. Whether this is so I do 

 "not know, and indeed do not believe it is so, but I 

 " found when there were many very young molluscs in 

 " a small vessel with aquatic plants, amongst which I 

 " placed a dried duck's foot, that the little barely visible 

 " shells often crawled over it, and then they adhered so 

 " firmly that they could not be shaken off, and that the 

 " foot being kept out of water in a damp atmosphere, the 

 " little molluscs survived well ten, twelve, or fifteen hours, 

 " and a few even twenty- four hours. And thus, I believe, 

 " it must be the fresh-water shells get from pond to pond, 

 " and even to islands out at sea. A heron fishing, for 

 " instance, and then startled, might well on a rainy day 

 " carry a young mollusc for a long distance. Now you 

 " will remember that E. Forbes argues chiefly from the 



