Some Hypertnetamorphic Beetles 37 



8. In the case of the Stylopidae the fact that the female lives 

 throughout life in the body of its host has and always will call 

 forth much interest. The question of fertilization is an unset- 

 tled problem. The ovoviviparous habit of Stylopidae is striking. 

 It is probably the only instance of such a habit among the insects 

 undergoing complete metamorphosis. 



9. The increasing degeneracy of the Heteromerous beetles as 

 their food increases in animal nature and as the parasitism de- 

 velops ; the occurrence of hypermetamorphosis among the para- 

 sitic forms ; the loss by Stylopidae of the principal Heteromerous 

 characters, rendering their determination difficult and their sys- 

 tematic position doubtful, are all points worthy of note. 



10. The hypermetamorphosis exhibited by these beetles is pe- 

 culiar to themselves. The first larva is a highly specialized larva 

 resembling certain adult Thysanura (C amp odea) . The second 

 and successive stages are more degenerate, becoming apodous. 

 The pupa is normal. 



11. While all of the above points are by no means new to 

 science, the evidence at hand has emphasized them — hence the 

 mention. 



189 



