138 LAND AND KRESIIWATER 



in " a very supercilious tone," has taken rae to task for overstepping 

 it, to describe species from Mala3-ana, Africa, the West Indies, &c. 

 My reply to him is this : 1 have, so far as my limited education in 

 Natural History has gone, tried to raise the ordinary standard of 

 much of the molluscan work in this country to something more 

 than mere shell descriptions ; but because I have included studies of 

 forms beyond the Indian borders to elucidate those within, I am 

 chided, and the reviewer thinks fit to be amusing at my expense by 

 mentioning Timbuctoo — I presume as a typical, out of the world 

 spot. I trust, however, the naturalist who may hereafter be 

 engiiged on the molluscan affinities of Timbuctoo and the Lake 

 Chad country will not neglect to notice whether any Abyssinian or 

 West- African forms extend into that area, and show how it may be 

 connected with Somaliland, Hocotra, and India. This narrow-minded 

 kind of criticism would equally condemn the writers of a "lievision 

 of the North- American Slugs " for alluding to the Himalayan genus 

 Anademis, one of the most interesting points in their paper. It 

 becomes impossible to limit the area of observation. Animal life 

 from the earliest times has been changing locally, and travelling 

 insensibly in different directions over vast segments of the earth's 

 surface: the chief interest in its study centres in how the creatures 

 of one segment, in this case snails and slugs, differ in their organi- 

 zation from those of another segment. Follow ing on this comes the 

 Geological History of the great segments, and how aud when they 

 were probably connected or separated. 



In Natural History we have to take all we can get, or we should 

 do so. So long as we studied nothing beyond the shell, particularly 

 fossil forms, workers were restricted to conchology, the limits of 

 which were more conveniently and naturally circumscribed, often 

 to the contents of a single geological horizon ; and as a knowledge of 

 the animals increased, so much the more could past physical features 

 bo intelligently read. When we are in possession of the animal, 

 and begin looking into anatomical differences, I see no other way 

 in which such study can be made both interesting and instructive 

 than by a liberal sx:ppl_y of drawings of the animals living (described 

 in this work) within the bounds of India, placed side by side with 

 those most nearly like them, or unlike them, the tenants of countries 

 outside it. It is quite immaterial whether the distance dividing 

 them be half the circumference of the earth or Timbuctoo itself. 

 If this investigation were only to prove all the species to be similar 

 something would have been gained, and we should come to the end 

 of our work ; fortunately the results are in the opposite direction, 

 and leave us some most absorbing points to ponder on. 



Malacologists are not a nimierous bodj', and for this very reason 

 it has been m}' endeavour, so far as my labours of hand and eye can 

 go, to render the work to some extent useful not only to naturalists 

 in India but to those wlio may be carrying on similar investigations 

 in Africa, Australia, and other parts of the world. There is still very 

 much to be learnt as to the actual extent of the area over which so 

 many 8]iecies are to be (nunil. and draAV a line round it. Take ibr 



