LITHOBIID^E. 673 



It is probable that the Centipedes and their allies appeared 

 at a much later period in the earth's history than the Chilog- 

 naths, as the earliest form of the present suborder known to us 

 is the Geophilus proavus* of Germar, from the Jurassic rocks, 

 whilst the oldest Myriopod, one of the Julidm, is, according 

 to Dawson, found in the lower Carboniferous rocks of Nova 

 Scotia, and Dr. Anton Dohrn has recently described a Julus 

 from the coal formation of German} 7 . 



CERMATID^E Leach. This group is characterized by having 

 only sixteen rings to the body, while the legs and antennae have 

 more numerous joints than usual. The head is large, very free 

 from the body, with compound eyes, as in the six-footed in- 

 sects, and long spiny palpi, while the tergites, or scuta, are 

 but eight in number, and there are nine pairs of spiracles. 

 The female ovipositor is forceps-like, while the corresponding 

 male appendages are style-like. The species are the 

 most gaily colored of the order, being striped along 

 the body and banded on the legs. Cermatia for- 

 ceps Rafinesque is greenish-brown, with three longi- 

 tudinal stripes of deep green. 



LITHOBIID^E Newport. In this and the remain- 

 ing families of this suborder the antennae are short, 

 and the eyes simple and sometimes wanting. In 

 the present family there are fifteen tergites, and the 

 antennae are longer than in the succeeding group. 

 In Lithobius the antennae are forty-jointed, and Fig. 645. 

 the head is broad and flat. The species of this genus attack 

 earth-worms, grappling with them for several hours, and after 

 killing them, suck their blood. They will, in confinement, de- 

 stroy each other. Their bite is poisonous to small articulates. 

 The European L. forficatus, according to Newman ("Ento- 

 mologist" 1866, iii, p. 342) is preyed upon by Proctotrupes 

 calcar of Haliday. Litliobius Americanus Newport (Fig. 645) 

 is a widely diffused species, and erroneously passes by the 

 name of Ear-wig. It is found everywhere, under sticks and 

 about manure-heaps, where it feeds upon insects and worms. 



* Since shown by Prof. Marsh to be an Annelid (Ischyracanthus). 

 43 



