406 Introduction to Animal Morphology. 



2. Hemerobiidae antennae like strings of pearls ; ocelli 

 none ; larva without suctorial claws ; ligula strong, undivided ; 

 C'hrysopa perla, the aphis-lion, emits a pungent odour. The 

 larvae of Sisyra live in Spongilla fluviatilis. Hemerobius has- 

 the last joint of the palp very long. Mantispa has the fore- 

 limbs predatory. 3. Sialidae head flat, horizontal; ocelli 

 present (none in Sialis) ; labium with a membranous, me- 

 sially-slit ligula, with terminal palp. Raphidia is called the- 

 camel-neck fly from the shape of its prothorax. 4. Panor- 

 pidae, Scorpion-flies head vertical, beak-like, with the cly- 

 peus at its extremity over the oval labrum, and a smaller 

 bidcntate mandible. 



Order 8. Trichoptera (Kirby] resembling the last, but 

 with hair-clad or scaly unequal wings, of which the hinder 

 pair are folded ; mandibles membranous; maxilla and lower 

 lip united into a valve-like flap, the palpi being nearly obso- 

 , or 2-5 jointed. The prothorax is reduced to a collar, 

 and the meso- is longer than meta-thorax. This includes one 

 family, Pliryi^aneidx' or Caddis-flirs, whose larvae by agglu- 

 tinating sticks, civic., make a case for themselves (spiral in 

 Mormonia). The males and females often differ in the num- 



'("joints in their maxillary palp. 



Order 9. Strepsiptera (Kirby) minute viviparous insects ; 

 parasitic on the abdomen of bee- and wasps. The males have 

 four wings, the anterior short and twisted ; the hinder large,, 

 fan-like infolding, and membranous, but with trifling power 

 of flight ; head short, vertical ; eye large, with few facets ; 

 antennae 4-6 jointed ; legs clawless, with a four-, three-, or two- 

 jointed tarsus. Females wingless, with a cephalothorax, and 

 a worm-like abdomen ; mandibles as two long, crossing 

 bristles ; maxilla fused to the labium, with a large two- 

 jointed palp ; labial palp none ; pro- and meso-thorax 

 short ; metathorax very large. The larvae have at first six 

 long legs, two tail bristles, and tracheal gills. They live 

 on wasp-larvae, and at their first moult their limbs are 

 lost, and they become worm-like, then attain their pupa 

 stage, and the female never leaves her pupa skin. The eggs 

 are developed scattered in the whole body. The eyes are 

 stalked in Stylops, sessile, fifteen-jointed in Elenchus. 



