12 PROCEEDINGS OP THE NATIONAL MUSEUM vol.73 



than long. There are 10 teeth in the pectinal comb in the male and 

 9 in that of the female. Nothing is known of the habits or dis- 

 tribution of the species, 



VAEJOVIS BOREUS (Girard) 

 NORTHERN SCORPION 



This scorpion (pi. 1, fig. 2), the most northern in its distribution of 

 any American species, is unmarked and dark yellowish brown. In 

 length it varies from 3.5 to 5 cm., and is of slender proportions. The 

 sting has a broad base which expands imperceptibly into the vesicle. 



Webster (1923) reported the species as occurring in North Dakota 

 in the region known as the " Bad Lands." His specimens were identi- 

 fied by the writer. Chamberlin (1924) identified a specimen of this 

 species taken at Medicine Hat, Alberta, Canada. It is not known for 

 sure, however, that V. horeus is actually established in Alberta. 

 Scorpions are constantly found under artificial conditions far north 

 of their natural range, where they have been transported by ship- 

 ments of household goods, fruit, lumber, or other materials. Such 

 specimens have been determined by the writer from Washington 

 and Philadelphia. It is well known, however, that in a state of 

 nature scorpions are not found in the environs of either of these two 

 cities. In the National Museum there are specimens from the fol- 

 lowing States: Arizona, Nebraska, Oregon, Idaho, Wyoming, Mon- 

 tana, South Dakota, and North Dakota. It is believed that this 

 material indicates fairly well the natural distribution of the species. 



Nothing is known concerning its habits other than the situations 

 in which they are found, which are those common to most scorpions. 



VAEJOVIS MEXICANUS Koch 



MEXICAN VAEJOVIS 



This scorpion is dark, reddish brown and is very granular. The 

 postabdomen is large, the vesicle rather slender and the sting short. 

 There are no ventral keels on the first two segments of the postabdo- 

 men. Length about 4.5 to 5.5 cm. 



The species is probably the most widely distributed of any in 

 Mexico occurring from Mexico City to the southwestern part of the 

 United States. In the mountainous regions of Mexico it breaks up 

 into two distinct subspecies, dugesi Pocock and stnithi Pocock. In 

 the National Museum collection there is but a single specimen which 

 was taken at Eagle Pass, Tex. In the Baerg collection there is a 

 specimen from Durango, Mexico, and two from Guatimape, Mexico. 



