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PROCEEDINGS OF THE SOCIETY. 



AN ORDINARY MEETING 



OF THE Society was Held at 20 Hanover Square, W., on 

 Wednesday, June 20th, H)17, Mr. E. Heron-Allen, F.L.S., 

 F.Z.S., ETC., President, in the Chair. 



The Minutes of the last Meeting, having been circulated, were 

 taken as read, approved, and signed by the President. 



The President intimated that there were no Fellowship candidates 

 to be balloted for, a circumstance which had not occurred for a great 

 many meetings. 



Mr. Martin Duncan then communicated a " Note on Fertilization 

 and Deposition of Ova in Forfumis depurator,'" in which he stated that 

 he had recently been able to oliserve the repeated deposition of fertile 

 ova by a female crab, after one copulation. 



The first Imtch of ova were deposited attached to each other in 

 typical manner. Subsequent depositions of the ova were separated 

 from each other and rested on floor of tank like grains of sand. Every 

 care was taken to preclude possibility of free spermatozoa being present 

 in the water of the tank containing the female crab. This rarely 

 observed phenomenon had been confirmed by Dr. H. C. Williamson and 

 Mr. H. J. AVaddington. 



The President did not consider that the question of the presence of 

 spermatozoa was of prime importance in the matter, because of the experi- 

 ments of Dorothy Jordan Lloyd upon the unfertilized eggs of female 

 Echini which had been kept, from birth, in sea-water passed through a 

 Berkefeld filter, bo excluding the faintest possibility of external agency. 

 By exciting those eggs with hypertonic solutions, she succeeded in pro- 

 ducing Echinoderm larvae which reached the pluteus stage and developed 

 into microscopic Echinoderms. Her results appeared in the "' Proceed- 

 ings " of the Royal Society ; and her experiments were checked and 

 repeated by Prof. McBride at the Imperial College of Science. Hence it 

 was known that parthenogenetic eggs could be fertilized, and he asked 



