MYRIAPODA. 



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about a hundred, are laid through the hole ; they are small 

 and covered with a gummy fluid. Then the hole is closed up, 

 and in twelve days the ova hatch. 



The genus Polydesmus forms a link between the two groups 

 of Myriapods. The species are flat and compressed, instead of 

 being rounded as in lulus. The nest is the same and the young 

 develop as in lulus, but the legs are on the second, fourth, and 

 fifth segments in the young specimens. Polydesmus complanatus 

 (fig. 46, 2), a pale purplish-white or rosy-tinted species, nearly 

 an inch in length when mature, has similar habits to lulus, 



Fir;. 4(). — Millepedks (1, Jllaitjuhts p2llclldlus ; 2, Polydesmus complavntvs). 

 Centipede (3, GeopMlus suhterraiwus). All slightly enlarged. 



feeding especially upon onions, and often causing their decay. 

 I have received notice of much damage caused by them in 

 greenhouses. 



The Chilopoda or Centipedes (fig. 46, 3) are all beneficial. 

 They are represented by four families in England {Lithobiiihc, 

 ScolopendridoB, Notophilidce, and Oeopldlidai), all being more 

 or less abundant. One of the commonest British species is Geo- 

 pMlus longicornis of Leach, which is a long, yellowish, thread- 

 like creature, often two inches in length. It moves rapidly, 

 with a curious, siniious, snake-like movement. The male spins 



H 



