3174 THE JOINTED ANIMALS 



The order Geophilomorpha, represented by the family Geophilidce, includes the 

 long worm-like centipedes, with the segments varying in number from thirty-nine 

 to over a hundred. There are no eyes and the short thick antennae are always 

 composed of fourteen segments. Each segment of the body, with the exception of 

 the first and last, bears a pair of stigmata and is double, an anterior portion being 

 cut off by a distinct joint. The Geophilidce, which are distributed all over the 

 world, with the exception of the polar areas, are subterranean in their habits, bur- 

 rowing after the manner of earthworms, upon which they almost wholly subsist. 

 Two exceptions, however, to this rule must be mentioned, namely, Linotcenia 

 maritima and Schendyla submarina, both of which have been obtained upon the 

 shores of Western Europe, beneath stones at low water mark. Although this is a 

 strange habitat for animals, air-breathing species typically terrestrial can withstand 

 immersion in sea water for many hours, and in fresh water from one to two weeks. 

 Many of the species emit a phosphorescent fluid from glands opening upon the 



GEOPHIUJS GRAPPLING WITH EARTHWORM. 

 (Natural size.) 



sternal surface of the segments. In Europe the time for the appearance of the 

 phenomenon is between the end of September and the beginning of November. 

 Although its import is not understood, it appears to be connected in some manner 

 with the mating of the sexes. A small reddish species (Linotcenia crassipes) is the 

 one most commonly found exhibiting this phosphorescence in England. 



Remains of fossil centipedes referable to the existing groups occur in amber 

 beds belonging to the middle portion of the Tertiary period; while mere aberrant 

 types have been discovered in the Paleozoic rocks of the United States. 



To a certain extent, connecting the centipedes with the millipedes and insects, 

 is the class Symphyla, containing the single genus Scolopendrella. This is repre- 

 sented by minute pale-colored creatures, with long thread-like antennas, fifteen or 

 sixteen body segments, and twelve pair of legs, each of which is armed with two 

 claws. It further differs from the centipedes in having only two pairs of jaws, 

 as in the millipedes. Scolopendrella, which includes two British species, also 

 occurs in North America, India, and Sumatra. 



THE MILLIPEDES Class Diplopoda 



Although millipedes and centipedes were formerly united to form the class 

 Myriopoda, it has been discovered that the characteristics in which they resemble 



