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itself transversely on tlie back of a large Oniscus, and allow the latter so to walk and 

 bear it about. The labium is much punctured, broad at the base and narrower in 

 front, where it is armed with twelve minute black teeth of equal size. The jaws are 

 attached to each side of the labium, and their tips cross each other when at rest, their 

 joints from the second to the fourth bear each two stigmata that look like pores or spi- 

 racles. The palpi have four joints, and are nearly setaceous and slightly hairy, the 

 third joint is longer than the second but shorter than the fourth. The outer side of 

 the jaws is even, but the inner side is angular. The eyes are granular and composed 

 of about sixteen tubercles. The legs are all formed for seizing and retaining. There 

 are sixteen dorsal segments, eight of them are large shield-like plates, becoming some- 

 what longer and narrower from the head to the tail, their fore border is straight, their 

 sides convex, and their hind border concave ; they are shining and nearly smooth, ex- 

 cepting a few very indistinct and irregular risings and depressions. Each of these has 

 following it, partly covered and sometimes quite hidden by its hind border, a very short 

 segment. In the male ? the part beyond the leg-bearing segments seems on the under- 

 side to consist of three portions ; the first large, nearly square, and broader than the pre- 

 ceding segment ; the second very short, and covere 1, except at the sides, by the first ; 

 the third consists of two lateral parts, each of which terminates in a small black horn, 

 armed with two spines. This species differs from Lith. laevilabrum in having less pi- 

 lose antennae, and less distinct transverse furrows on the four hind legs. The anten- 

 nae of the female are less pilose than of the male ; only one segment is visible beyond 

 that which bears the hindmost pair of legs, and the sexual organs are hidden. 



Genus. — Polydesmus. 

 Pol. complanatus. When very young and having only six legs it much resembles 

 Smynthurus and Armadillo, which, in the same stage of growth, associate with it in 

 abundance. When it is somewhat less than 3 lines in length, its legs form four waves 

 while walking. In its earlier life it has but 14, 15 or 16 segments, but when full 

 grown it comprises 20 dorsal segments besides the head, and has 62 legs, 28 double 

 pairs and 3 single pairs. It is at first pure frosted white, aftenvards dirty white, and 

 the alimentary canal is distinctly visible through the dorsal segments. When full 

 grown, the lengthening of the hind corners of each segment is first apparent on the 

 fifth from the head, and goes on increasing to the last. The sexual organs of the 

 male are under the seventh segment ; they are furnished with two long slender hooks, 

 each terminating in a claw, and set with teeth on the inner side of the basal part ; 

 they are transparent, bright, pale yellow, and are thus easily observed, the belly and 

 legs being white. In one stage of growth it has 3 single and 1 double pairs of legs. 



Genus. — Armadillo. 

 Arm. vulgaris. Swarms in great profusion amongst decaying vegetable matter. 

 It carries its young, 30 or more in number, attached to its body, which when rolled up 

 protects them from injury. They repose between and under the legs, and are most 

 abundant towards the head ; their colour is pale yellow or nearly white, the antennae 

 and legs and the margin of the border are quite white and nearly transparent, the eyes 

 are black. They are a line or less in length ; their bodies are soft, but the segments, 

 antennae, and nearly all the legs of the full-grown insect are already formed. When 

 they are left to provide for themselves, the dorsal segments become hard and shining 

 but are still white and semitransparent, and thus allow the internal functions to be 



