Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 FIG. 423.—Embryo of Stroiigylosoma (after E. Metschnikoff). their eggs in earth. The just-hatched young often pass through a metamorphosis, having at lirst only three or seven pairs of legs in addition to the antenna?, and a few somites without limbs (fig. 423). The young animals undergo numerous moults, and gradually increase in size: the extremities sprout out on the somites, which are already present. New somites are constricted oft' from the termi- nal one until the full number is co
Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 FIG. 423.—Embryo of Stroiigylosoma (after E. Metschnikoff). their eggs in earth. The just-hatched young often pass through a metamorphosis, having at lirst only three or seven pairs of legs in addition to the antenna?, and a few somites without limbs (fig. 423). The young animals undergo numerous moults, and gradually increase in size: the extremities sprout out on the somites, which are already present. New somites are constricted oft' from the termi- nal one until the full number is completed; the number of ocelli and of the joints of the antenna? is increased, and the resemblance to the sexual animal is gradually perfected. In other cases (Scolopendra, GeopldlidcK] the embryo already possesses the full number of appendages. Order 1.—CHILOPODA.* Myriapoda of usually flattened form, with long many-jointed antennce, and mouth parts adapted for predatory habits, with only one, pair of appendages to each segment. The body is long and usually flat- tened. The chitinous exoskeleton is hardened on the dorsal and ven- tral surface of each somite, consti- tuting the tergal and sternal plates, while on the sides of the somites it remains soft. In certain forms some of the terga develop to large shields, which over-lap the smaller terga of the intermediate somites (fig. 424). The number of legs is never greater than that of the sepa- rate segments, a single pair only being developed on each segment. The antenna? are long and many- jointed, and are inserted beneath the frontal margin. The eyes are simple or aggregated ocelli, except in the genus Scutigera which has facetted FIG. ±21.—LitJwIjiHs forficafits (after C. L. Koch). Kf, Poison claws. * Newport, 'Monograph of the Class Myriapoda. order Chilopoda,'' Lhinfean x, XIX.
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