COLLECTING AND PRESERVING INSECTS BANKS. 



125 



Fig. 185.— The Cattle tick, Marga- 

 ropus annulatus. (after pack- 

 ARD.) 



one can hardly see them without a glass. They make galls on the 

 leaves of trees and shrubs. These galls have an opening which 

 distinguishes them from most insect 

 galls, excepting those of the Ilomoptera. 

 There are three other smaller groups 

 of Arachnida. The Solpugidse, or ringed 

 spiders, sometimes called vinagarettes 

 or vinagarones, have the abdomen seg- 

 mented, the palpi are simple, and the 

 mandibles are very large and prominent. 

 The Phrynida are flat creatures with 

 segmented abdomen connected to the 

 cephalothorax by a slender pedicel. The 

 palpi are spiny, and the first pair of 

 legs very long and fine. The whip- 

 tailed scorpions (Thelyphonida) have a 

 segmented abdomen with a fine fila- 

 ment at the tip. Their palpi are very 

 heavy and spiny. They are also called vinagarones and mule- 

 killers, but are not poisonous. Most of the Arachnida are preda- 

 ceous or parasitic on animals, but quite a 

 number of mites are phytophagous. In most 

 of our spiders the jaws are so small and weak 

 that they can not pierce a person's skin, and 

 those that can do so have not a poison suffi- 

 ciently strong to cause much pain. The 

 tarantulas of the West 'and South should not 

 be handled, but the cases of dangerous bites 

 from these creatures are extremely few. The 

 ticks attach themselves to people, and some- 

 times their bite causes much pain, and one 

 kind carries a disease. The red bugs, the 

 young of harvest mites, are an intolerable 

 nuisance in many parts of the South. The 

 sting of our scorpions is rarely more severe than 

 that of a wasp or hornet. 



The Myriopoda include two very distincl 

 groups which really are not related to each 

 other. One, the centipedes or Chilopoda, are 

 like long wingless insects with a pair of logs 

 to each segment of the body. The house 

 centipede, Scutigera (Cermatia) forceps (fig. 

 187), is an example of this group. Its bite 

 is often quite severe. Its poison comes from 

 a large pair of jaws under the head, which is developed from 

 the second pair of legs. They occur under leaves and stones, 



Fig. 180.— One of the gall- 

 mites, Eriopuyes. 



