STRUCTURE 



47 



Order V. Pauropoda. 



A pair of limbs to each segment. Antennae branched. 

 Eyes few or none. Labrum and labimii indistinct. Creuital 

 orifice at the base of the second pair of limbs. Free dorsal 

 scutes. Nine pairs of feet (always ?). Some segments with 

 sensitive hairs. Last segment the smallest. 



Family 1. Pauropidae. 



Body slender. Dorsal scutes smooth. Limbs long and projecting from 

 the lateral margins of tlie body. Colour pale. 



The Structure of the Myriapoda. 



Having now given a short view of the classification of the 

 Class, I will proceed to give a general accoimt of their structm-e, 

 the variations in which have led to the divisions into the various 

 Orders and Families. Their structm-e shows resemblances to 

 several widely different classes of animals. One cannot help 

 being impressed with their likeness to the Worms, at the same 

 time they have affinities with the Crustaceans, and still more 

 with the Insects. In the latter class the likeness of the Thy- 

 sanuridae to Scolopendrella and Pauropus have induced a cele- 

 brated Italian anatomist, Professor Grassi, to claim the former as 

 the ancestors of the Myriapoda. 



Myriapods have a body which is segmented, as it is termed ; 

 that is, composed of a number of more or less similar parts or 

 segments joined together. 



One of the most important characteristics which distinguish 

 Myriapods from other Arthropoda is the fact that they possess 

 on the posterior segments of the body true legs which are 

 jointed and take part in locomotion. The head is in all cases 

 quite distinct from the body, and may be regarded as a number 

 of segments fused together into one mass. Their heads are 

 always provided with a single pair of antennae and mouth 

 appendages, consisting of an upper lip, a pair of mandiUes or 

 ■jaws, and one to two pairs of maxillae. The mandibles resemble 

 those of Insects, and are strongly toothed. In the Chilognatha 

 a pair of maxillae are fused so as to form a single oval appendage. 

 In the Chilopoda they each consist of a single blade bearing a 



