Dugesiella lientzi (Girard). ' 375 



by the front legs of the male, that it almost forms a right angle 

 witli the abdomen. The front legs remain lifted but they, too, show 

 a complete relaxation of all muscles. The sperm is injected into 

 one of the receptacles, the walls of which are rieh with chitinous 

 sense organs of special structure. The coitiis lasts about half a 

 minute. Then the palpus is withdrawn. If the male intends to 

 introduce the other palpus he continues to hold the fangs of the 

 female and after resting for a few moments, begins once more with 

 the second stage of the coiirtship, i. e., he drums with the patellas 

 of the palpi upon the sternum of the female until he manages to 

 introduce the second palpus. 



When the coitus is finished both male and female begin to 

 back slowly away from each other (Fig. 12), the former still holding 

 his front legs stretched out in front of him between the front legs 

 of the female. The relaxation of muscles in the legs of the female 

 gradually disappears. In the next moment both male and female 

 make a sudden jump away from each other and go their separate 

 ways. 



As long as the palpi of the male are lilled with sperm, he 

 invariably courts the female if brought into contact with her, but 

 when his palpi are empty he will not court, nor will any amount 

 of teasing or forcible pushing him toward her, make him do it. He 

 does all in his power to escape even when the female is sexually 

 excited. Several days elapse after mating before he will construct 

 another spermweb and tili his palpi again with sperm. The instinct 

 of propagation with its complicated set of actions, necessary for the 

 preservation of the species but endangering the life of the male as 

 an individual, disappears with the accomplished mating and the 

 inhibited instinct of seif protection comes again into play and 

 dominates his behavior. 



