BEHAVIOR OF ANURA TOWARD COLLOIDAL DYES 



TABLE 2 

 Bufo lentiginosus 



(5) on June 12, three (3) on June 13, four (4) on June 14 and 

 seven (7) on June 15), dye granules were invariably found in the 

 cytoplasm of the cell in certain typical tissues (table 1, column V). 



Experiment 2 (table 2). Thirty-three (33) larvae of Bufo lentig- 

 inosus (controls of Experiment 1) were placed in a 1:1000 solu- 

 tion of trypan blue on June 4, one day later than in Experiment 1, 

 and four days after fertilization. These larvae measured about 

 five millimeters in length and the external gills were just begin- 

 ning to make their appearance. Certain of these larvae were 

 transferred daily from the dye solution, from June 5 to June 8, 

 inclusive, to tap water in which they remained twenty-four hours 

 before killing and fixation. 



An examination of serial sections of eight (8) larvae killed on 

 June 6, five (5) killed on June 7 and seven (7) killed on June 8, 

 showed that no dye granules had been stored in the cytoplasm of 

 any cell in these twenty (20) larvae. In one (1) larva killed on 

 June 7 and two (2) larvae killed on June 8 dye was stored in the 

 epithelium of a few pronephric tubules. These three larvae 

 formed the only exceptions, however, in which dye had been 

 deposited in any of the tissues among the larvae of this experi- 

 ment which were killed previous to June 9. In all of the ten (10) 

 larvae which were killed on June 9 (ninth day after fertilization) 

 dye granules were invariably found in the cytoplasm of the cell 

 in certain typical tissues. 



Experiment 3 (table 3). This experiment differs from Experi- 

 ment 2 only in the circumstance that the larvae of Bufo were 



