a new Type of Centipede. 9 



unequal. One bears a single, the other two, long, many-jointed 

 appendages. The mouth consists of two pairs of minute or- 

 gans ; the anterior ones toothed, the posterior pointed. Be- 

 tween the second pair of legs are two processes, which probably 

 form part of the generative organs. 



The author has been able to trace the development. The 

 smallest specimens met with have three pairs of legs, and the 

 number increases at each moult; but it is remarkable that 

 whereas two pairs are acquired in the first, so that the number 

 rises from three pairs to five, at the subsequent moults a single 

 additional pair only is obtained. 



A second species of the genus was found with the first. It 

 is, however, much rarer, and differs in the form of the antennae. 



Sir John then proceeded to make some remarks on the sys- 

 tematic position of the Myriapoda, which he regarded as form- 

 ing a class, and he expressed the opinion that the genus now 

 described approached the other Articulata more nearly than any 

 Myriapod hitherto known. Nor did he think that Pauropus 

 could be placed in either of the two great groups of Myriapoda, 

 which may be characterized as follows : — 



Chilopoda. Antennae with not fewer than fourteen seg- 

 ments. One pair modified into powerful footjaws. Gene- 

 rative organs opening at the posterior end of the body. Legs 

 in single pairs. 



DiPLOPODA. Antennae with not more than seven segments. 

 No footjaws. Generative organs opening at the anterior part 

 of the body. Legs, after the first six, arranged in double 

 pairs. 



Pauropus, at first sight, looks most like a Chilopod. Its ac- 

 tivity, the compactness of its body, the dorsal plate, and elon- 

 gated hind legs give it much the appearance of a very minute 

 Lithobius. A closer examination, however, does not favour this 

 view. The antennae have only five segments; the powerful 

 footjaws are absent ; and the generative organs appear to open 

 anteriorly. 



Nor can Pauropus be classed among the Diplopods. It is true 

 that the eight posterior legs correspond to four dorsal plates; 

 nevertheless it is evident that in reality each pair belongs to a 

 separate segment, as may clearly be seen if we look at the 

 animal from beneath. In one sense, this is true also of the Di- 

 plopods ; but they invariably have the legs attached by double 

 pairs, while those of Pauropus are equidistant. Moreover in 

 all Diplopods the first three pairs of legs are distinguished 

 from the rest by possessing each a distinct segment, whereas 

 in Pauropus this is the case with the first pair only. In Di- 



