No. 598] THE STERNUM IN SCORPIONS 001 



Ischnurinae African, Asiatic and neotropical (Opistha- 

 canthus elatus is the single neotropical species) ; the Dip- 

 locentrina? neotropical and Asiatic (a single genus with 

 two species from eastern Asia). 



All scorpions belonging to the large family Ihithuhr 

 have a distinctly "triangular" sternum with converging 

 sides and truncated apex. The family is naturally di- 

 vided into two large subfamilies. Of these the Buthime 

 may be regarded as belonging to the Old World, since 

 of its 14 genera a single genus and species [Ananteris 

 bahanl) is found in South America. The subfamily Ocn- 

 trurina' includes four genera. The genus I, so met r us is 

 characteristic of the Old World but its commonest species, 

 I. maculatus, is cosmopolitan and occurs in Florida. Ha- 

 waiian Islands, South America, etc. Z alii us is South 

 American. Titiu.s is neotropical, although one -pedes, T . 

 /lorifhi mis, occurs in southern Florida. The largest 

 genus, Centrums, is represented by some of the com- 

 monest species in the southern United States and the sub- 

 tropical and tropical America. 



Let us fix our attention for a moment on the distribu- 

 tion and characters of two genera of scorpions common 

 to the United States. One is Vejovis (of the family 

 Vejovidse) and is represented in this country by six spe- 

 cies; the other is Centrums (of the family Buthidae) and 

 is represented by seven species. Vejovis belongs more to 

 the southwest and west. It is distributed through Cali- 

 fornia, Nevada, Utah, Arizona, New Mexico and Texas 

 and extending northward into Idaho and Nebraska. A 

 single species, V. carolinus, is found in the southeast. It 

 occurs as far north as South Carolina and spreads south- 

 ward to the Gulf states and Texas. Except possibly this 

 species, the other species of Vejovis occur also in Mex- 

 ico where the genus is represented by four additional 

 species which do not occur in the United States. 1 have 

 besides, in mv private collection, a new species of Vejovis 

 from Terra del Fuego. Centrums belongs more to the 

 southeast. A single species (C. exilicauda) occurs in 



