170 



INTRODUCTION. 



like a Crabro or Pemphredon larva ; and its appearance apparently 

 deceives the wasps themselves, for they are, it is thought, hostile 

 to the perfect insect *. 



Symbius blattarum is a very remarkable insect and is parasitic 

 on cockroaches (BlattidjE). The male is winged, bnt the female 

 is larviform and apterous, and neverjeaves the body of the cock- 

 roach ; its life-history is not fully^known. 



The family contains more than 100 species, the greater number 

 of which inhabit temperate climates ; four or five species of 

 Emenadia occur in the Indian region. 



Family 85. MELOIDiE (including LYTTIDyE). 



Head vertical, strongly and suddenly constricted ai some distance 

 behind the eyes, with an abrupt neclc ; antenna' variable, usually 

 eleven-jointed, inserted before the eyes at the sides of the front ; pro- 

 thorax nearly always narrower at the base than the elytra^, not mar- 

 gined; anterior and middle co.ro> large, conical, and contiguous ; 

 anterior coxed cavities large, confluent, open behind ; posterior coxee 

 transverse, prominent, nearly contiguous; elytra variable; abdomen 

 with six free ventral segments; each claw with a long appendage 

 closely applied, beneath it, or toothed ; integument more or less soft. 



This well known family is in part remarkable for the very- 

 curious hypermetamorphosis in their life-history, and the various 



Fig. 74. — Horia dehyi (natural size). 



forms of larva and pupa, beginning with the active triungulin 

 which infests bees and by them is carried to their nests ; and in 

 part for the fact that many of its members contain the substance 



* Some authors, however, believe that it secretes a fluid agreeable to the 

 wasps amongst which it is found (Ent. Nachr. xi, p. 34) ; this, however, seems 

 doubtful : if it be true, then it seems quite possible that the perfect insect may 

 obtain the opportunity of ovipositing within the nest. 



t In Cejjhaloon it is only as broad at the base as the elytra. 



