24 



AN INTRODUCTION TO ENTOMOLOGY 



of ScolopendreMa 

 (After Hansen). 



32, mx) resemble in a striking degree the maxillas of insects, consisting 

 of a long stipes, (5), which bears a minute palpus, (^), and an outer 

 and inner lobe; Vae second maxillce or labium (Fig. 

 32, /) also resembles the corresponding part of the 

 more generalized insects, being composed of a pair 

 of united gnathites. 



The legs of the first pair are reduced in size and 

 in the nimiber of their segments. The other legs '^pophlVynx ^ (h) 

 consist each of five segments; the last segment andmaxillulae(m) 

 bears a pair of claws. Excepting the first two 

 pairs of legs, each leg bears on its proximal seg- 

 ment a slender cylindrical process, the parapodium (Fig. 34, p). 

 These parapodia appear to correspond with the styli of the 

 Thysanura. 



At the caudal end of the body there is a pair of 

 appendages, which are believed to be homologous 

 P'^^^'f^^'^ with the cerci of insects (Fig. 35, c). 



A striking peculiarity of the symphylids is that 



Fig- 34- \^% °^ they possess only a single pair of tracheal tubes, 

 Scolopendrella; f^ , ^ . f f . •. . -i • -•. 



p, parapodium. which open by a pair of spiracles, situated m the 



head beneath the insertion of the antenna. 



The members of this class are of small size, the 

 larger ones measuring about one-fourth inch in 

 length. They live in earth under stones and decay- 

 ing wood, and in other damp situations. Imma- 

 ture individuals possess fewer body-segments 

 and legs than do adults. 



Less than thirty species have been described; 

 but doubtless many more remain to be discovered. 



The known species are classed in two genera: Fig. 35.— The caudal 



Scolopendrella and Scutigerella. In the former the ^n^, o^ the body of 



Scolopendrella; i, 

 posterior angles of the terga are produced and leg; c, cercus (After 



angular; while in the latter they are rounded. Latzel). 



A monograph of the Symphyla has been published by Hansen ('03). 



Class MYRIENTOMATA 

 The Myrientomatids 



The members of this class are small arthropods in which the body w 

 elongate, as in the Thysanura, fusiform, pointed behind, and depressed; 

 it may be greatly extended and retracted. The antenncB and cerci are 



