172 



DWIGHT ELMER MINNICH. 



TABLE II. 



SHOWING THE RESULTS OBTAINED WITH Lucilia sericata UNDER THE FOLLOWING 

 CONDITIONS OF STIMULATION: A, WATER VAPOR PLUS TARSAL CONTACT WITH 

 WATER; B, WATER VAPOR PLUS TARSAL CONTACT WITH PARAFFIN OIL; C, 

 WATER VAPOR ONLY. 



Because of the error involved in the first set of experiments 

 with Phormia, another and third set was undertaken on these 

 species. In these experiments the apparatus used in the first 

 two sets was discarded for Syracuse watch glasses containing 

 cotton pads soaked in water or oil. The animals were tested: 

 (i) on water soaked cotton, where they were subjected to tarsal 

 contact with water plus water vapor; (2) on oil soaked cotton, 

 where they were subjected to tarsal contact with oil (no water 

 vapor) ; (3) over the water soaked cotton but not in contact with 

 it, where they were subjected to the stimulus of water vapor only. 

 The results (Table III.) show 100 per cent, response in position 



1 (column A, Table III.) and but 5 per cent, response in position 



2 (column B}. After the trials in positions i and 2 were made, 

 the animals were tested in position 3 where they gave 1.4 per 

 cent, response (column C}. In order to show that the experi- 

 mental procedure had not rendered the animals less responsive, 

 each animal was finally tested in position I again immediately 

 after each trial in position 3. The result (column D) was 100 

 per cent, response. The low per cent, obtained in position 3 

 could not, therefore, be attributed to any changed condition in 

 the animals. 



The results of these experiments show two facts clearly. 



