III.] THE EARTHWORM. 27 1 



a series of transparent nucleated protuberances — 

 centrally into a large non-nucleated mass. 



y. The same during the later maturation stages. 

 Nuclear division has gone on with rapidity, and 

 the central mass is now surrounded by a great 

 number of small nucleate bodies. Examine care- 

 fully the protoplasmic investments of these — each 

 is prolonged out into a short filament. 



S. The ripe spermatozoa; aggregates of filiform struc- 

 tures resulting from the nucleate bodies above 

 described. Each is enlarged at its attached end 

 to form a 'head,' within which the elongated 

 nucleus is contained. Focus to the centre — the 

 non-nucleated mass has remained passive and 

 unaltered. 



e. Look for free spermatozoa. 



