JOURNAL OF CONCHOLOGY. 



Vol. 13. APRIL, 1910. No. 2. 



THE IMPORTANCE OF THE ANIMAL IN THE LAND 

 MOLLUSCA, SHOWN BY CERTAIN EVOLU- 

 TIONARY STAGES IN SOME GENERA 

 OF THE ZONITID^. 



(Presidential Address delivered at the Annual Meeting, October i6th, 1909). 



By Lt.-Colonel H. H. GODWIN-AUSTEN, F.R.S. 



I IMAGINE there can be very few field conchologists, who, after a 

 certain number of years' work, do not find themselves taking occasional 

 notice of the animals of the shells they are collecting, attracted either 

 by colour, form or habit. As such observations increase, notes and 

 comparisons are made of the form of the foot, of the eye-tentacles 

 and other external parts of the body of species met with, until at last 

 the interest is divided between the shell and the animal. Having 

 reached this stage, a further advance is in view of the conchologist, 

 an advance, if he makes it, he will never regret, viz. : the examination 

 of the internal characters, bringing about a knowledge of the general 

 plan of the organs of the body, and the functions they have to perform. 

 When this stage of research has been reached, interest in the mollusca 

 is more than doubled, the ultimate results are far reaching, extending 

 and leading on to phylogeny and physiology. 



Having myself gone through these stages from the purely concho- 

 logical to the more detailed malacological, it is my excuse this evening 

 for selecting the latter as the subject of my address to this Society, and 

 I shall try to show by a few examples that the animal is well worthy of 

 attention. I will go even further to show that the exclusive study of 

 the shell, which represents after all, only what the animal constructs 

 in its lifetime, is unsatisfactory, because it leads to no true result. 

 Species after species may be created on shell character with all minute 

 differences in the shell described, yet their accurate classification based 

 on this single character must be faulty, and deductions having regard 

 to distribution and relationship of comparatively little weight. Deduc- 



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