478 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 50. 



Head and body without pseudocelli; eyes present or absent; postantennal organ,! 

 usually present; furcula present or absent; sense-organ of third antennal 

 segment with sense-rods, but without sense-cones and outer papillae. 



Head prognathous; unguiculi present or absent; furcula not extending 

 beyond the ventral tube; dentes not divided into two segments; not 

 ringed distally, not bowed. 

 Mouth parts mandibulate, not projecting in a cone; mandibles with a 

 molar surface; furcula present; anal spines usually present. 



Subfamily Achorutinae Borner, 19016 (p. 478). 

 Mouth parts mandibulate or piercing-suctorial, projecting in a cone in 

 most of the genera; mandibles small or absent, without molar sur- 

 face Subfamily Neanurinae Borner, 19016. 



Anal segment relatively small; supra-anal valve rounded, not 



bilobed; furcula present or absent; segmental tubercles absent. 



Tribe Pseudachorutini Borner, 1906 (p. 498). 



Anal segment relatively large; supra-anal valve bilobed; unguiculus 



absent; furcula absent; segmental tubercles present; buccal cone 



present; anal spines absent. . Tribe NEANURiNiB6rner,1901rf(p. 507). 



Head hypognathous; unguiculi absent; furcula extending beyond the ventral 



tube; dentes two-segmented, ringed distally, bowed outward. 



Subfamily Podurinae Borner, 1906 (p. 513). 

 Head and body with pseudocelli; eyes absent; postantennal organs almost always 

 present and well developed; mouth parts mandibulate, mandibles with molar 

 surface; furcula absent or rudimentary; sense-organ of third antennal segment 

 with sense-rods, sense-cones, and often with outer papillae ; anal spines usually 

 present Subfamily Onychiurinae Borner, 1906. 



Snbfamily ^CHORXJTHSTAE BOrner. 



Achorutini Borner, 1901a. 

 Achorutinae Borner, 19016. 

 Hypogastrurinae Borner, 1906. 



KEY to genera OF ACHORUTINAE. 



1. Furcula present; eyes present 2. 



Ful^ula absent; eyes absent; postantennal organs present; unguiculus present; 



anal spines minute or absent; white or yellow Willemia Borner. 



2. Eyes eight on each side; postantennal organs present; furcula well developed. . .3. 

 Eyes five on each side; postantennal organs absent; unguiculus absent; furcula 



often more or less reduced; anal spines two, usually minute. XenyZ/aTullberg, p. 495. 



3. Postantennal organs with four to seven peripheral tnhercles. Achondes Templeton, 4. 

 Postantennal organs each with a single large elongate suboval tubercle; un- 

 guiculus absent; anal spines absent Beckerella Linnaniemi. 



4. Unguiculus present Achorutes Templeton, p. 478. 



Unguiculus absent Suhgenus SchottellaSchixEer, p. 494. 



Genus ACHORUTES Templeton. 



Achorutes Templeton, 1835. — Tullberg, 1872. 

 Hypogastncra Bourlet, 1842. — Borner, 1906. 



Eyes eight on each side of the head. Postantennal organs each 

 with four (seldom more) })cripheral tubercles. Antennae cylindrical, 

 four-segmented. Mouth parts mandibulate; mandibles with a well- 



