310 THE president's ADDRESS. 



character of all living creatures. Not tlie less wonderful is the 

 illustration afforded by the same author of the morphological differ- 

 ences produced by varying the conditions under which animal life 

 may be developed in the case of Lymnea stagnalis. Removing 

 the patch of eggs, so familiar to all of us who keep a fresh-water 

 aquarium, and dividing it into four portions, he found that by 

 limiting the supply of water in which the subsequent development 

 took place,- the length of the shell was progressively increased 

 in proportion to the volume of water in which each portion was 

 placed. These are facts which have a most important bearing on 

 the growth and development of higher forms of life than either 

 Artemia or Lymnea, and worthy the earnest attention of every 

 student in the Club ; for when animal life, either of man or the lower 

 animals, is developed under cramped conditions, modifications take 

 place not favourable to the normal growth of the frame, and that 

 man or that animal, subject to these conditions, becomes stunted and 

 dwarfed, such development always being attended by morphological 

 changes which are equally abnormal. This fact should always be 

 borne in mind in assigning any fresh form of life to any particular 

 species, as the danger of creating a Lymnea grown in a small 

 quantity of water into a new species is very great, when its altered 

 size would be only the result of the narrow area under which the 

 diversity was developed. 



Again, what a rich store of interest will be found in the study of 

 the comparative anatomy of insects, and the various changes taking 

 place in their organs in their progress from the larval condition to 

 the perfect imago ; in exemplification of this, see the diversity of 

 character to be met with in only one organ — take the gizzard as an 

 instance ; and what a variety is presented in the cockroach, the flea, 

 the cricket and the staphylinus, enough to repay for all the careful 

 and delicate dissection necessary to demonstrate them ; we might 

 also point out a similar diversity in the anatomy of insect salivary 

 glands. By taking up these studies we not only provide ourselves 

 with highly interesting amusement, but we can help those who are 

 engaged in these subjects as a profession, and whose time for work 

 is greatly limited. If we take care that every fact is accurately 

 observed, and our observations are verified by good preparations, our 

 Club will be doing most serviceable work to advance the progress 

 of biological studies. Of course you will be met by the remark that 

 all this has been done before by our continental brethren ; but, how- 



