ART. 9 SCORPIONS OF WESTERN UNITED STATES ^EWING 9 



in a jar with a deep layer of soil at the bottom and a small piece of 

 wood inclined against one side of the jar. The idea in placing the 

 wood in the jar was to give the scorpion a place to conceal itself as 

 it normally does in nature. One edge of the wood, however, was 

 lifted enough to allow easy vision of the specimen when the jar was 

 held to the light. 



During the very first day the scorpion started digging in the sandy 

 soil. This was accomplished by sudden backward jerky movements 

 of one or two legs on a side at a time. The first and second or the 

 second and third legs of a side were most frequently used. After a 

 considerable amount of excavation had been made she remained com- 

 paratively quiet in the hole under the wood. Although offered several 

 roaches as food, none were eaten. During the latter part of May she 

 came out from under the piece of wood and did not return until she 

 had dug a tunnel similar to those of gophers. Inside of this tunnel 

 she rested contentedly. This specimen, as well as others kept in 

 captivity, at first showed much activity during the night. When 

 the lights were turned on the scorpion would be found scrambling 

 up the sides of the jar, lifting itself as high as possible by the cauda, 

 then falling back again. 



HADRURUS AZTECUS Pocock 



|. MEXICAN HAIRY SCORPION 



Pocock (1902) described as new a species taken at Jalapa, Mexico. 

 In general appearances it is almost exactly like the well known 

 H. hirsutus of the Mexican border, but differs from the latter in a 

 number of minor characters. In aztecus the frontal area of the 

 carapace is studded with large round granules instead of being 

 closely and finely granular; the terga are mostly smooth in front 

 and mesially instead of being finely and coarsely granular as in 

 hirsutus. There are several other differences. 



The distribution and habits of this species have not been studied. 

 There are no specimens of it in the United States National Museum, 

 and it is not represented in the Baerg Mexican collection. 



Genus VAEJOVIS Koch 



Vaejovis is similar to Had^ntrus but is easily distinguished from 

 the latter by the absence of the spinelike tooth on the ventral side of 

 the movable finger of the chelicerae. 



The species of Vaejovis are smaller than those of Hadrurus and, 

 with but a single exception in the United States, are much less 

 hairy. In this genus is to be found a majority of the North Amer- 

 ican members of the family Vaejovidae. One of its species far out- 

 ranges all other scorpions to the northward in America being found 

 up to, or possibly over, the northern boundary of the United States, 

 78958—28 2 



