MYRTAPODA. 229 



far greater activity is indispensable, and accordingly we find the 

 segments of the body, and the extremities appended to them, ex- 

 hibiting a perfection of structure adapted to greater vivacity and 

 more energetic movements. 



This is at once evident upon a mere inspection of their out- 

 ward form ; the individual segments composing the animal are 

 much increased in their proportionate dimensions, and, instead of 

 being cylindrical, each division of the body is flattened and pre- 

 sents a quadrangular outline. In order to give greater flexibility to 

 the body, instead of the semi-crustaceous hard substance which forms 

 the rings of the Julus, the integument is composed of a tough and 

 horny substance, forming two firm plates, one covering the back, the 

 other the ventral aspect of the segment, while all the lateral part 

 is only incased in a flexible coriaceous membrane with which the 

 individual rings are likewise joined together. Such an external 

 skeleton is obviously calculated to give the greatest possible free- 

 dom of motion, and thus to enable the Scolopendra to wind its 

 way with serpent-like pliancy through the tortuous passages in 

 which it seeks its prey. 



(273.) The ventral chain of ganglia belonging to the nervous 

 system presents a series of nervous centres of dimensions proportioned 

 to the increased bulk of the segments in which they are lodged, and 

 thus fitted to direct the movements of more perfect limbs. The 

 legs, therefore, as a necessary consequence, become proportionably 

 powerful, divided into distinct joints, and provided with muscles 

 calculated to bestow on them that activity essential to the pursuit 

 and capture of active prey. Thus, then, by a simple concentra- 

 tion of the nervous masses composing the abdominal chain of 

 ganglia, we have the slow-moving and worm-like Julus, which we 

 have seen to be, in consequence of its feebleness, restricted to live 

 upon roots and dead substances, converted into the active and 

 powerful Scolopendra, well able to wage successful war with the 

 strongest of the insect tribes, and not unfrequently formidable 

 from its size even to man himself. 



(274.) The mouth of the Scolopendra is a terrible instrument 

 of destruction ; being provided not only with horny jaws resembling 

 those of insects hereafter to be described, but with a tremendous 

 pair of sharp and curved fangs, ending in sharp points, and per- 

 forated near their termination by a minute aperture, through which 

 a poisonous fluid is most probably instilled into the wound in- 

 flicted by them. It is to this structure that the serious conse- 



