151 



I^-L. 



107. Supplements well separated acuticauda de Man, I88O (s) 



Supplements closely approximated , . . vestibulifer Micol,, 1922 (s) 



108. Lip region not set off, indistinct ....<. 109 



Lip region distinct 110 



109. Vulvar region striated ,..,.,.. -"mlvostriatus Stef ., 1923 (s) 

 Vulvar region not striated luganensis Steiner, 191^ (moss) 



110. Length about 2.0 mm.j supplements within range of spicula 



alpinus Steiner, 19li| (s) 



Length about 1.2 mm.j supplements anterior to spicula Ill 



111. Lips set off by constriction .... productus Th. & Swang., 1936 (s) 

 Lips set off by depression arcus Th. & Swang., 1936 (s) 



112. Tails digitate and subdigitate 113 



Tails conoid to hemispherical 125 



113. Lips continuous with neck contour llU 



Lips distinct and prominent 115 



llU. Head abruptly truncate; terminus acute 



truncatus Th. & Swang., 1936 (?) 



Head somewhat rounded; terminus blunt . nitidus Th. & Swang., 1936 (s) 



115. Tails digitate, usually dorsally recurved II6 



Tails subdigitate, usually with terminal core 119 



116. Prerectum length twice the corresponding body width 117 



Prerectum length equal to, or less than, the corresponding body 



width 118 



117. Lips angular, conspicuous irritans Th. & Swang., 1936 (s) 



Lips not angular centrocercus de Man, I88O (s) 



118. Terminus acute granuliferus Cobb, 1893 (s) 



Terminus bluntly digitate . obesus Th. & Swang., 1936 (s) 



119. Length 2.5~3.5 mm 120 



Length under 2.0 mm 122 



120. Spear aperture occupying one-third the spear length 

 varicaudatus Thorne 



Spear aperture one-half or more of the spear length 121 



121. Spear aperture one-half the spear length 



capitatus Th. & Swang., 1936 (s) 



Spear aperture three-fourths the spear lenp;th 



sublabiatus Th. & Swang., 1936 (s) 



