Body very long, 200 to 350 rings; alternate principal and subsidiary rings. A pair of legs to each principal ring. No eyes. Maxillary palps {46}very thick. Compact or very short limbs. The terminal point of the last limb without claws. Family 4. _Geophilidae._ Body long, 80 to 180 rings, principal and subsidiary. No eyes. The maxillary palps not compact, and with first joint large. Last joint of the last pair of legs with a sharp claw. [Illustration: FIG. 27.—_Geophilus longicornis._ (From C. L. Koch, _Die Myriapoden_.)] Order III. SCHIZOTARSIA. The tarsi of all the legs multiarticulate. The eyes facetted. Peculiar sense organ beneath the head. Family 1. _Cermatiidae_ (_Scutigeridae_) Antennae with unequal number of joints. Body rings, each with one pair of legs. Dorsal scutes not so large as ventral. Limbs long and multiarticulate. (Fig. 17, p. 35). Order IV. SYMPHYLA. Myriapods resembling Thysanura. A pair of limbs to each segment. The antennae are simple and multiarticulate with unequal joints. Eyes few. Mandibles short. One pair of maxillae. No maxillipedes. Genital orifice in the last segment of the body. A single pair of tracheae. Two abdominal glands on the posterior part of the body. Two caudal appendages. Free dorsal scutes. Ventral scutes often with parapodia. Family 1. _Scolopendrellidae._ With the characters of the Order. {47}Order V. PAUROPODA. A pair of limbs to each segment. Antennae branched. Eyes few or none. Labrum and labium indistinct. Genital orifice at the base of the second pair of limbs. Free dorsal scutes. Nine pairs of feet (always?). Some segments with sensitive hairs. Last segment the smallest. Family 1. _Pauropidae._ Body slender. Dorsal scutes smooth. Limbs long and projecting from the lateral margins of the body. Colour pale. THE STRUCTURE OF THE MYRIAPODA. Having now given a short view of the classification of the Class, I will proceed to give a general account of their structure, the variations in which have led to the divisions into the various Orders and Families. Their structure shows resemblances to several widely different classes of animals. One cannot help being impressed with their likeness to the Worms, at the same time they have affinities with the Crustaceans, and still more with the Insects. In the latter class the likeness of the Thysanuridae to _Scolopendrella_ and _Pauropus_ have induced a celebrated Italian anatomist, Professor Grassi, to claim the former as the ancestors of the Myriapoda. Myriapods have a body which is segmented, as it is termed; that is, composed of a number of more or less similar parts or segments joined together.