INSECTA. 

 MYRIOPODA. 



309 



CENTIPEDES. 

 CHILOPODA. 



MILLIPEDES. 

 DIPLOPODA (or CHILOGXATHA). 



Carnivorous. 

 Poisonous. 

 Body usually flat. 



One pair of appendages to 

 each segment. 



Many-jointed antenna}. 

 Toothed cutting mandibles. 

 Two pairs of maxillre, usually 

 with palps. 



The first pair of legs modified 

 as poison claws. 



A single genital aperture on the 

 second last segment. 



Examples. Scolopendra. 

 Lithobius. 

 Geophilits. 



Vegetarian. 

 Harmless. 

 Body cylindrical. 



By the imperfect separation of 

 the segments, all but the first 

 three seem to have two pairs of 

 appendages each, and also two 

 paired ganglia, and two pairs of 

 stigmata (tracheal openings). 



Seven-jointed antennoe. 

 Broad masticating mandibles. 

 A pair of maxillre fused in a 

 broad plate, usually four-lobed. 



No poison daws. 



Genital apertures open an- 

 teriorly. 



Examples. Jit I us. 



Polyxemis. 

 Glomeris. 



In the order Symphyla (Scolopendrella) there are not more than 

 twelve segments, and there is only one pair of tracheae, which open on 

 the head. Scolopendrella is in several ways like the primitive insects 

 known as Thysanura. In the order Pauropoda (Pauropus)^ there are 

 ten segments, and the antennae are branched. 



Third Class of Tracheata Antennata. INSECTA. 



Insects occupy a position among the backboneless 

 animals like that of birds among the Vertebrates. The 

 typical members of both classes have wings and the power 

 of true flight, richly aerated bodies, and highly developed 

 respiratory, nervous, and sensory organs. Both are very 

 active and brightly coloured. They show parallel differ- 

 ences between the sexes, and great wealth of species within 

 a narrow range. 



