CYTOPLASMIC INCLUSIONS IN MALE GERM CELLS 

 OF THE FOWL TICK, ARGAS MINIATUS, 

 AND HISTOGENESIS OF THE 

 SPERMATOZOON 1 



D. B. CASTEEL 



ONE TEXT FIGURE AND EIGHT PLATES 



CONTENTS 



Introduction 643 



Material and methods 644 



History of the spermatocytes and spermatids 646 



General account 646 



True mitochondria 650 



Extra-nuclear bodies 651 



Vesicular bodies and oil drops 653 



Formation of the spermatozoa 656 



Summary and conclusion 662 



Bibliography 666 



INTRODUCTION 



This paper is more particularly concerned with the cyto- 

 plasmic elements found in the male germ cells of the chicken 

 tick, Argas miniatus, with special reference to the occurrence 

 and behavior of the mitochondria throughout the complete his- 

 tory of spermatogenesis, from spermatogonia to mature sperma- 

 tozoa. As will be noted, the nuclear components of the cell are 

 considered only in so far as they bear relations to extra-nuclear 

 substances. 



In view of the fact that the spermatozoa of many Acarines are 

 of relatively large size and of markedly atypical form it is sur- 

 prising to find that the literature dealing with them is but slight 

 in amount. The more important studies upon the histogenesis 

 of tick spermatozoa are those of Christophers ('06), Norden- 



1 Contribution from the Zoological Laboratory of the University of Texas, 

 No. 129. 



643 



