PREFACE. 



numerous to mention individually) who, of late years, have 

 done so much towards a fuller understanding of the subject, 

 and from whose published works and papers I have largely 

 culled much interesting and valuable information. My last 

 word, in conclusion : should the young collector be ever at 

 a loss to name a snail or a slug, let him send the specimen 

 to me ; enclosing the return postage, when I will do all in my 

 power to help him over his difficulty. 



" Go, child of nature, to thy mother's breast, 

 And learn the lesson she can teach so well ; 

 No longer in the lap of folly rest, 

 But hear the truths that nature loves to tell." 



J. W. W. 



MIDDLESEX HOSPITAL, LONDON, W., 



AND MITTON, STOURPORT, WORCESTERSHIRE. 



