( XV ) 
Hah. Australia. Loc. Mount Gib, near Bowral, N.S.W. 
(alt. over 2000 ft.), (G. A. Waterhouse)." 
Mr. Oswald H. Latter read a paper entitled " Further 
Notes on the Secretion of Potassium Hydroxide by Dicranura 
viniiia (imago) and similar Phenomena in other Lepidoptera." 
The paper was illustrated by the oxy-hydrogen lantern. 
Professor Meldola said that when some time ago Mr. 
Latter made his first communication to the Society on this 
subject the result was received with some hesitation by 
chemists. He (the speaker) had, however, never doubted the 
correctness of the conclusions as the evidence seemed to him 
quite satisfactory, and he was glad that Mr. Latter had now 
confirmed and extended his observations. He thought that, 
in view of the small quantity of material at his disposal, the 
concordance in the titration experiments was quite remarkable 
— differing only in the second decimal — and he congratulated 
the author upon the results obtained. It had now been 
definitely proved for the first time, so far as he knew, that 
free potassium hydroxide was secreted as a product of 
physiological activity in the animal kingdom, and the present 
instance was all the more interesting because the same insect 
in the larval condition secreted (as had been proved by 
Professor Poulton) a 37 per cent, solution of formic acid as a 
means of defence. He asked the author whether the 
alkalinity of the contents of the alimentary tract was limited 
to those species which made cocoons or whether it was a 
general character which had been specialized for a particular 
purpose in the species under observation. He suggested also 
that it might be worth while in future experiments to 
examine the solution after titration for organic acids, as there 
might be present combined potassium in addition to the free 
hydroxide. 
Dr. Dixey said he thought it might be worth while to 
bear in mind, with reference to Mr. Latter's very interesting 
observations, that the pancreatic secretion is in all animals 
strongly alkaline ; though this was, of course, in no case due 
to the presence of a free caustic -alkali. 
Mr. Blandford, Mr. Merrifield, and Mr. Latter continued 
the discussion. 
