HOW TO KNOW THE IMMATURE INSECTS 



27a. Terga expanded laterally; body oval; antenna club-shaped. 

 Fig. 199 Family SCYDMAENIDAE 



It includes more than 1,200 species of small 

 insects. They mostly occur in moss, under 

 bark or in ants' nests. Scarcely anything ap- 

 pears to be known of the biology of the fcan- 

 ily. 



scydmaenid 



27b. Terga not expanded; antenna not club-shaped. 



Fig. 200 Family PSELAPHIDAE 



The species mostly live in ants' nests and the adult 

 bears a resemblance to ants. The biology of the 

 larvae is little known. More than 3,000 species have 

 been described. Their size is small. 



Fig. 200. Eup- 

 lectus confluens 



Lee. 



28a, Hypermetamorphosis present; mandible without molar 

 part; maxillary mala short, thick, almost vestigial; 

 gular area present; cerci absent. Fig. 201 29 



Hypermetamorphosis is a condition that prevails 

 among a relative small percentage of insect species. 

 Some of the instars are radically different from each 

 other in habits and form or in some cases addi- 

 tional instars occur between the full grown larva 

 and the adult. 



Fig. 201. Ven- 

 tral QspecT of 

 head. 



28b. No hypermetamorphosis; 

 than in 28a 



different combination of 



characters 

 31 



84 



