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mer is generally membranaceous, tliat of the latter coriaceous, and the transition from 

 the one to the other is manifested by the Chilognatha and the imperfect state of Crus- 

 tacea. Julus pulchellus loves darkness as well as moisture, and conceals itself from 

 the light as speedily as it can. When it has but one pair of crimson spots, they are 

 situated just behind the 8 or 10 legs that are all it has, and occupy scarcely half the 

 length of the body ; the segments being about ten in number. When it has 7 pair of 

 spots, its length is about H line, and comprises 16 segments. When full grown the 

 segments are 50 and the legs 94 in number ; the segments are finely striated. 



Julus terrestris. The black or grey colour of Julus is not in the outer segments, 

 but is caused by their food and by the oil and coloured matter which they secrete; 

 thus when the segments of Julus terrestris are empty, they are transparent, white, or 

 pale yellow, like as the whole of the live insect when very young. It seems to have 

 but one regular unvarying pace in walking ; its hindermost legs first step forward, 

 their example is followed by the next pairs, till the motion is communicated to those 

 next the head, and the movements of all together resemble waves rolling onward, or 

 the cilisE of Vorticella ; four or five undulations are visible at one time. When crawl- 

 ing it moves its head slightly from side to side, and feels its way with its antennae, 

 which have some resemblance to those of the larvae of Silpha, which latter differ not 

 very widely from Julus in their habits of life. A noise being made it stops, raises its 

 antenna, bends them at an angle downwards, and seems to listen for a Avhile, but al- 

 though the noise is continued, it soon resumes its walk. When first touched it rolls 

 into a spiral form, of which its head is the centre, and thus forms either one, two or 

 three layers of concentric circles, the highest of which is the least, and above it the 

 head is sometimes raised perpendicularly. It sometimes repeats this process when 

 again touched or disturbed, but at last it ceases not to walk however much interrupted 

 or handled. It shows most activity when taken out of the earth, and jerks, twists and 

 wriggles its body with the muscles of its numerous segments, as an eel or a serpent 

 does with its dorsal vertebrae. Its length is about f of an inch ; ash-colour, the sides 

 mottled with white ; the belly, legs, front of the head and the antennae are white ; 

 there is a black stripe down the back, and each segment, except the four next the head 

 and the five next the tail, has a dark reddish brown spot on either side, surrounding 

 the pore and corresponding to the crimson spots of Julus pulchellus. The segments 

 are about 52 in number, and each is finely striated longitudinally, but its base, which 

 when the insect is in action passes under the hind margin of the preceding segment, is 

 smooth, as also is the head and the greater part of each segment adjoining it. When 

 the insect begins to move, its antennae are first vibrated, then the motion extends to 

 the adjoining legs, and is continued to the hinder, the process being reversed when it 

 walks. The anus is large, and forms two valves which open laterally. The eyes are 

 seated behind the antennfe, have an irregular triangular shape, and are tuberculate, 

 the tubercles being about sixteen in number. The antenna are 6-joiuted, semitraus- 

 parent, pubescent, slightly clavate ; the first joint is half the length of the second; 

 the third a little shorter than the second, and the fourth bears the same proportion to 

 the third ; the fifth is slightly longer than the fourth ; the sixth is oval, thicker than 

 the fifth but not more than half its length. A suture extends across the vertex from 

 eye to eye, so that the head appears to consist of two segments that are anchylosed to- 

 gether. The body from the head to the tail increases in thickness, though very slowly 

 and gradually. The segment behind the head is larger than the others, is very con- 



