132 BULLETIN 168, UNITED STATES NATIONAL MUSEUM 



Plate 12 

 Guthriella muskegis: 



113. Dorsal aspect of left mucro of female, X 493. 



114. Dorsal aspect of left mucro of male, X 507. 



115. Dorsal setae of first abdominal segment of female, X 300. 



116. Dorsal aspect of left lateral lobe of fourth abdominal segment of male, 



X 143. 



117. Clavate fringed tubercle of male, X 487. 



118. Capitate seta of male, X 773. 



119. Dorsal aspect of fourth antennal segment of right side of male, X 247. 

 Proisotoma (Ballistura) schbtti: 



120. Right fore foot, X 387. Specimen from California. 



121. Left hind foot, X 407. Specimen from New York. 



122. Left mucro, X 673. Specimen from California. 



123. Left mucro, X 673. Specimen from California. 



124. Left mucro, X 673. Specimen from New York. 



125. Dorsal setae of first abdominal segment, X 230. 



Plate 13 

 Proisotoma {Ballistura) eivingi: 



126. Eyes and postantennal organ of left side, X 673. 



127. Left hind foot, X 1,053. 



128. Left dens and mucro, X 673. 



129. Left aspect of tenaculum, X 673. 



130. Dorsal setae of first abdominal segment, X 673. 

 Proisotoma (Ballistura) excavata: 



131. Dorsal aspect of head, X 193. 



132. Eyes and postantennal organ of right side, X 673. 



133. Dorsal aspect of right antenna, X 400. 



134. Sense organ of third antennal segment of left side, X 1,067. 



135. Left hind foot, X 847. 



136. Dorsal aspect of dentes and mucrones, X 673. 



Plate 14 

 Proisotoma (Ballistura) excavata: 



137. Right mucro, X 847. 



138. Dorsal setae of first abdominal segment, X 673. 

 Proisotoma (Ballistura) laticauda: 



139. Eyes and postantennal organ of left side, X 667. 



140. Sense organ of third antennal segment of left side, X 980. 



141. Left hind foot, X 667. 



142. Left dens and mucro, X 467. 



143. Left mucro, X 653. 



144. Right mucro, X 504. 



145. Left aspect of tenaculum, X 571. 



146. Dorsal setae of first abdominal segment, X 485. 

 Archisotoma besselsi: 



147. Eyes and postantennal organ of left side, X 480. 



148. Left hind foot, X 793. 



149. Part of left hind femur and tibiotarsus, X 673. 



