Proceedings of 

 the United States 

 National Museum 



SMITHSONIAN INSTITUTION • WASHINGTON, D.C. 



Volume 117 1965 Number 3514 



REVISION OF THE MILLIPED GENERA 



BORARIA AND GYALOSTETHUS 



(POLYDESMIDA: XYSTODESMIDAE) ' 



By Richard L. Hoffivian ^ 



Introduction 



The present paper is the sixth part of a monographic study of the 

 diplopod family Xystodesmidae begun in 1956. In recent years, 

 largely through the efforts of LesUe Hubricht, the quantity of available 

 study material in this group has been increased vastly and the prepara- 

 tion of additional generic synopses correspondingly has been accel- 

 erated. Completion of the series is anticipated within the next four 

 years. 



The two genera considered in the following pages belong to a group 

 that has been recognized recently (Hoffman, 1960) as the tribe 

 Rhysodesmini. Species of this tribe are of interest in their departure 

 from the usual xystodesmid structural relationships. Normally in 

 this family species differ chiefly in gonopod form; here the various 

 species differ strikingly in body structure while the gonopods remain 

 essentially similar even among different genera. This condition is 

 particularly true of the nominal genera centered around Rhysodesmus 



1 Studies supported by grants (G-9805 and G-21519) from the National 

 Science Foundation. 

 * Radford College, Radford, Va. 



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