392 



2. Apical abdominal segment terminating in a pair of long, tapering, 



baekwardly directed thorns; first abdominal segment with the 

 postspiracular hairs as long as head and thorax combined 

 (Spogostylum) 3 



— Apical abdominal segment usually more or less truncated and with 



an upwardly and baekwardly directed upper process and one or 

 two smaller protuberances below it ; first abdominal segment with 

 the postspiracular hairs much shorter than head and thorax 

 combined 5 



3. Head Math 4 long thorns on upper anterior margin, the lower one 



on each side with a small protuberance at base on under side ; the 

 pair of thorns on lower portion of central line of face large, their 

 bases contiguous ; hairs on head and thorax very long ; laterad of 

 the short thorns the transverse armature of dorsal abdominal seg- 

 ments 2-6 consists of 2-3 long, widely placed rounded hairs 



Spogostylum anale. 



— Head with 6 short, stout thorns on upper anterior margin 4 



4. The pair of thorns on lower portion of central line of face small, 



their bases subeontiguous ; hairs of abdomen, except those of 

 verse armature of dorsal abdominal segments 2-6 consists of 12-20 



long, closely placed, flattened hairs 



Spogostylum simson (p. 393) . 



— The pair of thorns on loAver portion of central line of face large, 



their bases, subeontiguous ; hairs of abdomen, ex;cept those of 

 basal segment, normal Spogostylum olhofasciatum (p. 395). 



5. Antero-lateral margins of head each with 1 strong thorn, upper an- 



terior margin with 2 such tliorns, making 4 in all ; laln'um with a 

 bifid thorn CJirysantlirn.r fulvoJiirta. 



— Antero-lateral margins of head each with 2 strong thorns, upper 



anterior margin with 2 such thorns, making 6 in all 6 



6. Labrum with a strong bifid thorn; wing with a median subcostal 



protuberance ApJioehantus mus. 



— Labrum unarmed 7 



7. The stout thorns on dorsal abdominal segments turned up at bases 



and apices 8 



— The stout thorns on dorsal abdominal segments turned up at apices 



only 11 



8. Lower lateral cephalic thorn with a palp-like organ projecting on 



its under surface at base, the apex of which is armed Avith several 

 hairs Bomhylius. 



— Lower lateral cephalic thorn without a palp-like organ on under sur- 



face / 9 



9. Apical 3 segments without the dorsal transverse series of short 



thorns, armed only with slender hairs ; no slender hairs inter- 

 spersed between the short thorns of median portion of series on 

 other segments Argyromoeha oedipus. 



