455 



petroleum. Dr. Pulleine exhibited a phallocrypt from 

 Southern Dutch New Guinea, near the British border. It 

 was made of bamboo, carved and incised into the resemblance 

 of a man. 



Illustrations to Transactions. — The President spoke 

 of the congratulations that he had received on behalf of the 

 society upon the excellence of the three-colour illustrations 

 appearing in the last issue of the Transactions. They were 

 the work of the Donald Taylor Collotype Co., of South Aus- 

 tralia. A water-colour painting of the shell was made by the 

 artist and photographed in colours. Three negatives were 

 prepared. The light from the painting entering the camera 

 lens was filtered through a blue screen, which gave a yellow 

 negative; through a green screen, which gave a red negative; 

 and through a red screen, which gave a blue negative. Each 

 of these negatives was printed on ordinary bromide paper, 

 and gave a print with dark shades where the colour was most 

 intense, and light shades where it was less intense. Each of 

 these positive prints was then used to furnish an ordinary 

 half-tone negative, and these negatives were used to print 

 upon three metal plates, which, being treated with chemical 

 corrosives, provided three blocks for printing the three several 

 colours. Yellow, red, and blue inks, corresponding exactly 

 with the complementary screens which had been employed 

 in the original three-colour photography, were used in the 

 final printing, the first impression being the yellow, the second 

 the red, and the third the blue, the three superposed giving 

 "the tints of the original watercolour. Of course great care 

 and skill were needed to maintain an exact balance between 

 the three colours, and between these and the tints of the 

 screens, and an exact superposition of the three separate 

 prints, technically known as the maintenance of the register. 



Mr. W. H. Selway referred to the danger there was of 

 •damage being done to the glaciated rocks at Hallett's Cove 

 from holiday-makers when the Willunga Railway was opened 

 to traffic, and suggested that the Council should consider the 

 question of their protection. 



Papers. — ''An Evolution of the Sphere," by G. A. 

 Goyder, F.C'.S., read by Professor R. W. Chapman, M.A., 

 B.C.E. ; ''Description of New Genera and Species of Aus- 

 tralian Chalcidoid Hymenoptera in the South Australian 

 Museum," by A. A. Girault, communicated through A. M. 

 Lea, F.E.S. 



Ordinary Meeting, June 12, 1913. 



The President (J. C. Verco, M.D., F.R.C.S.) in the 

 <;hair. 



