72 MICHIGAN ACADEMY OF SCIENCE. 



divisions as regards size and we took this to indicate tliat it requircti 

 three rears for tlie complete development of the larva?. The individuals 

 taken this spring could practically all be grouped as follows: Those 

 nearly fully developed measuring from seventeen to twenty cm. in 

 length, those measuring from nine to eleven cm. in length, and those 

 from three to six cm. in length. Last fall two of the larvtB taken 

 measured about fifteen cm. and all the others were less than ten cm. 

 long. 



All the work doue by us on this interesting furm Avas directed by Prof. 

 Jacob Reighard and whatever of success we attained was due to his 

 suggestion, although the details w^ere left to us to work out. 



