OUR FRKSn-WATER MOLI.OSCA. 157 



but thcat even this is liable to objection, for many birds and animals are 

 led by pure instinct to vary their habits according to circumstances. Still, 

 it will do, as well, perhaps, as any other that could be formed. But, when 

 we find individuals performing actions that other individuals do not perform, 

 and led by evident motive, some exhibiting affections, and others passion.«, 

 not shared by the generality of their kind, and led by those affections and 

 those passions to perform actions exactly such as man, men guided by 

 reason, would perform, what are we then to say? ''Equidem credo quod 

 sit divinitus illis ingenium," says Virgil. For instance: — A dog, in Scot- 

 land, has been in the habit when his master went to market with him to 

 take the next train, (from Irvine to Ayr,) visit the cattle-market, and 

 not finding him, to come back again. 



C To be continued.) 



OUR FRESH-WATER MOLLUSCA. 



BY E. M. A. 



GoxcHOLOGTSTs have hitherto, in a certain measure, neglected our Land 

 and Fresh -water Mollusca. It is true that their inferiority in beauty to 

 their marine brethren cannot be denied, and the collector of them will 

 regret the sight, and sound, and smell of the glorious sea, that cheered 

 and invigorated him while collecting the marine species. Of late years, 

 however, this branch of Natural History has been more favourably regarded. 

 Montagu was far too good a naturalist to be ignorant of its value. Old 

 Dr. Turton's "Manual," with many inaccuracies, is still a good book; and 

 in the beautiful work of Professors Forbes and Hanley, this division of 

 Mollusca is treated with as much respect as its more conspicuous relatives. 



Moreover, when you turn your attention to this part of creation, you 

 will be convinced that our Land and Fresh-water Shells hardly yield in 

 beauty to the marine species; that their delicacy of texture and shape, 

 and especially the exquisite adaptation of each to that position which it 

 is destined to fill in the great scheme of creation, are well deserving of 

 your notice and study. 



I can, from my own experience, testify that a collection of Land and 

 Fresh water Shells — call them snail-shells if you like! — forms of itself a 

 most interesting little cabinet. Of nearly one hundred and twenty species 

 found in Great Britain, but few — say a dozen — are so rare as not to be 

 procured with a little trouble. Many of the rarer species are abundant in 

 the localities where they are found, and I have discovered that exchanges, 

 of mutual advantage, may easily be effected with brother-naturalists in most 

 parts of the kingdom. 



