25-3 



to hold together the partich's of soil. Where the cocoons were 

 made on the sides of the vials I was ahle to see throngli the 

 thin weh and note the transformations inside. The following 

 gives a hrief snnnnary of the varions stages: 



March 7th 



egg laid 



March 11th 



Hatched 



March 17th 



Pupaecell 

 formed 



March 20th 



Pupated 



March 25th 



Pupae 



slightly dark 



color 



March 28th 



Pupae very 

 dark color 



March 29th 



emerged 



This makes a total of 22 days from eg;g to adnlt ; other 

 records gave from 21 to 20 days, hence the life cycle is about 

 3 or 4 weeks. 



ACTIVITY OF Al)UI/rS. 



Fleas that emerged April 15th were put into a large glass 

 iar with a yonng rooster. A careful chart was made of the 

 top of the head, showing the distribution and sex of each of 

 the fleas. It was found that the males move about during the 

 night, being attached in different positions each morning — 

 usually near females. They began dying after 2 days and 

 at the end of 6 days all were dead — many of them in situ, 

 with their beaks attached to the skin. The females, unless 

 disturbed, remained attached in their original positions. After 

 18 days the first one died a natural death. The others died 

 from three to four weeks after emergence, and a single female 

 lived 40 days, producing eggs up to the time of her death, 

 and, upon dissection, the ovaries were found to contain numer- 

 ons developing ovules. 



EC4G LAYING. 



Gelatin capsules were attached over several of the females 

 to determine their egg-records. It was found that most of 

 the eggs were laid at night, — under favorable conditions as 

 many as 40 being deposited, while during the day only 2 or 

 3 were ])roduced. Another interesting observation was that 

 the females with males located near them laid many more eggs, 

 and that their record dropped off decidedly, after 2 days, if 

 the males were removed. Experiments were tried of intro- 

 ducing new males with females that had ceased laying, and it 



