CHAPTER XIV. 



PERIPATUS, MYRIOPODS, AND INSECTS. 



Series Arthropoda. Sub-division Tracheata 

 Antennata. 



Classes Prototracheata. — Peripatus. Myriopoda. — Centipedes 

 and Millipedes. Insecta. — Insects. 



These three classes form a series of which winged insects 

 are the climax. The type Peripatus is archaic, and hnks 

 the series to the Annelids ; the Myriopods lead on to the 

 primitive wingless insects. 



We may speak of the series as Tracheata Antennata, for 

 all breathe by tracheae — tubes which carry air to the recesses 

 of the body — and all have antennae. 



First Class of Tracheata Antennata — Prototracheata, 

 including one genus, Peripahis. 



General Characters. — The body is worm-like in form, 

 soft skinned, and without external segmentation. 



There is a pair of prominent pre-oral antennce. 



The true appendages are — a pair of jaivs in the tnouth, a 

 pair of slime secreting oral papilla, numerous pairs of short, 

 imperfectly jointed legs, each with two claws, and a pair of 

 anal papilla. The legs contain peculiar (coxal) gla?tds. 



Respiration is effected by numerous trachece, whose openings 

 are somewhat scattered on the surface of the body. The heart 

 is simply an elongated dorsal vessel with valvular openings. 

 There is a series of excretory tubes or nephridia. The halves 

 of the ventral nerve cord are widely separate. 



The single genus Peripatus is represented by numerous 



