PLATE 6 



EXPLANATION OF FIGURES 



28 See plate 7. 



29 Young spermatozoon from smear preparation, drawn to one-half scale of 

 the other drawings. The head of the inner tube has advanced half way down the 

 outer tube. The elongated nucleus is migrating through the gelatinous envelop 

 toward the distal end of the outer tube. The finger-form process has diminished 

 in size. 



30 Spermatozoon from smear preparation in the condition in which it is 

 transferred in the spermatophore from the male to the female tick. Both the 

 nucleus and the mitochondria-bearing end of the inner tube lie near the distal 

 end of the outer tube. The innei." tube will later break through the outer at the 

 point a. 



678 



