154 JOURNAL OF CONCHOLOGY, VOL. 9, NO. 5, JANUARY, 1899. 



were much appreciated by the members of our Society attending the 

 Congress. 



In these utilitarian times it is becoming every day more self-evident 

 that to preserve our native fauna we must be able to show what place 

 and use the various species composing it are intended to occupy and 

 fill in nature. We are all of course agreed that every species of 

 animal has its own special office to discharge and fills some special place 

 in the scheme of nature. In many cases, however, it is not easy, except 

 for those who are conversant with the whole life-history of a species, to 

 convince an untutored mind that to keep the proper balance of nature 

 such species of animal life must be preserved. In the case of our 

 mollusca generally, it must be admitted that to a casual observer the 

 slimy form and crawling habits of these animals are at first sight both 

 repulsive and repugnant to man, and man's natural instinct is at once 

 to destroy such forms of life as blots in creation, and as probably in 

 some way damaging to man's welfare. In the short time at my dis- 

 posal to-night I therefore propose to set before you some of the natural 

 functions performed by some of our British land and freshwater mol- 

 lusca, so as to entitle them to the protection of man within due bounds 

 rather than to destruction and extermination. 



The uses of the mollusca may then I think be arranged under four 

 principal heads : — 



I. — As scavengers and helps to sanitation and to the preservation 

 of the health of man. 



II. — As food and medicine for man. 



III. — As food of other animals. 



IV. — As articles of merchandise, and so contributing to the wage- 

 earning of men. 



I. — As scavengers and helps to sanitation, and to the preservation of 

 the health of man. 



In considering this part of my subject I have carried out certain 

 experiments and investigations, to prove as far as possible in what 

 numbers and to what extent our native mollusca are found on land 

 and in our inland waters. It is of course well known that some species 

 are arboreal in their habits to a certain extent, such as Umax mar- 

 ginatus, Helix nemoralis, H. hortensis, Buliminus montanus, B. 

 obscurus, and the Clausilitz — others require shade and retirement, 

 such as H. hispida, H. aatleata, and many of the Pupce — others are 

 found in damp places under stones and decaying wood and in damp 

 buildings, such as the Zonitidse — others on warm dry cliffs, such as 

 H. pisana and H. acuta — others on dry downs and sand-hills, such as 

 H. virgata, H. itala, etc. — others are marsh-dwellers, as the Succinece 

 — others, again, are subterranean, such as the Testacellce and Ccecilioides 



