392 



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



backwardly 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 backwardly 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 with 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 aiiale. 



— 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 subcontiguous ; 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 lower portion of central line of face large, 



their bases, subcontiguous; hairs of abdomen, except those of 

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



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



terior margin with 2 such thorns, making 4 in all ; labrum with a 



bifid thorn Clirysantlirax fulvoliiria. 



Antcro-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 Aplioehantus 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 pro.i'ecting on 



its under surface at base, the apex of which is armed with 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 Argyramoehn oedipus. 



