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ENTOMOr.OGICAL PROGRAM. 



On Some Interesting Archaic Insects (with exhibitions). 



BY DR. R. J. TILLYARD, 



Chief of the Biological Department, Cawthron Institute of 

 Scientific Eeseareh, Nelson, New Zealand. 



The insects exhibited consist partly of archaic Aiistrahan 

 and New Zealand forms and ])artly of other interestin,^ forms 

 gathered during' my present trip around the world, which will 

 be completed next month when I return to Xew Zealand. I'or 

 convenience they may be dealt with under the separate Orders 

 which they represent. 



Order Thysani'ra. 



A female specimen of a gigantic Japygid, belong'ing to the 

 g'enus Hctcrojapyx (sp. undescribed ), from near Sydney, 

 N. S. W. 



Specimens of this insect have been found up to fully two 

 inches in length. They live in the soil often at considerable 

 depths, and behave very much like the common centipedes of 

 the g'enus Scolopcndra, their mode of progression, in spite of 

 the absence of the paired abdominal leg's, being- very similar to 

 that of the centipedes. They also have the peculiar habit of 

 working" backwards and tipwards in the soil until the forceps 

 lies level with the surface, when they will lie in wait for their 

 prey, which they seize with the forceps, dragging" it under 

 ground and devouring it when dead. 



Two interesting' points about the morphology of this fine 

 insect may be mentioned here. The paired stylets of the 

 abdomen show a definite coxite and two distal joints. Hence 

 they would appear to be definitely the serial homologues of the 

 thoracic legs ; i. e., they are endopoditcs instead of epipodites, 

 as has been formerly stipposed, on the analogy of the unjointed 

 stylets of other Thysanura with the epipodites of the thoracic 

 legs of MacJiUis. The arrangement of the spiracles, as in all 



Proc. Haw. Ent. Soc, IV, No. 3, Septeiiil)er, 1921. 



