30 THYSANOURA. PARASITA LOUSE. 



LESSON II. 



AP'TERA. ORDER or THYSANOU'RA. 



ORDER OF PARASI'TA. Louse Ticks. 



ORDER OP SUCTO'RIA. Flea Chigre. 



ORDER OF COLEOP'TERA. Characters Division Pentame'rans 

 Cicin'dela Carabus Gyrinvs, or Water-beetle Fire-fies 

 Glow-worm Borers Derme'stes May-bugs Scarabeus 

 Heterome'rans Blistering -files Teterame'rans Weevils 

 Trime'rans Lady-bug. 



ORDER OF ORTHO'PTERA. Characters Earwigs Mole-crick- 

 ets Crickets Grasshoppers Migratory Locusts. 



1. Hexapods or true insects comprise all those which have 

 three pairs of legs: they all have a head distinct from the thorax, 

 and the abdomen has no extremities attached to it ; some are 

 apterous (without wings),. others are winged. 



2. Although apterous insects are not very numerous, they form 

 three distinct orders ; namely, Thysanou'ra, Parasi'ta, and 

 Sucto'ria. 



ORDER OF THYSANOU'RA. 



3. The Thysanourse (from the Greek, thusan, bushy, arid 

 oura, tail) are small wingless insects that do not undergo meta- 

 morphosis ; the abdomen terminates in filiform appendages, or is 

 furnished with organs by means of which they are enabled to 

 leap. 



ORDER OF PARASI'TA. 



4. We give the name of parasites (hanger on) to those apterous 

 insects which do not undergo metamorphosis and whose abdomen 

 is without any appendage ; their mouth is chiefly internal and is 

 armed with a kind of sucker ; their body is flattened, 



and, as their name indicates, they live upon other ani- 

 mals ; but they are only found on mammals and birds. 

 Lice (Pediculus), of one of which the annexed figure 

 (21) is an enlarged representation, and dog-ticks 

 (Ricinus) belong to this order. Their eggs are known. Fig. 21, 

 under the name of nits. LOUSE. 



1. Do all insects possess wings ? 



2. What orders of insects are wingless ? 



3. What are thysanou'ra ? 



4. Give examples of insects of the order Parasita. 



