446 INVERTEBRATE MORPHOLOGY. 



4. Order Eedipalpi. 



The order Pedipalpi includes two genera, PJirynus and 

 Thelyphonus, both of which are inhabitants of the warmer 

 regions of the earth. The cephalothorax is unsegmented ; 

 the abdomen in Phrynus is elongated and oval, and composed 

 of eleven segments showing little differentiation of form, 

 while in Thdyphonus there are twelve segments, the last 

 three of which are much smaller than 

 the others and bear a long, many- 

 jointed terminal filament. The cheli- 

 cerse are not chelate, but the terminal 

 joint may be flexed upon the basal 

 one and contains the duct of a poison- 

 gland which opens at its extremity. 

 The pedipalps in Phrynus are long 

 and leglike, though richly provided 

 with spines, and terminate with un- 

 gues, but in Thelyphonus they are rel- 

 atively short and stout with a flexible 

 terminal joint as in the chelicerae ; 

 ' in both genera the basal joints of the 



¥ia.20i.-T7wlyphonmcau- ^^^ pepipalps are fused. The first 



datus (from CnviEK). ^ \ '- '^ 



leg IS long and slender and termi- 

 nates in a filament-like structure, the other three pairs being 

 typical walking-legs. 



Four stigmata occur, one pair situated in the second and 

 another in the third abdominal segment, and they open into 

 cavities containing lung-books. The" digestive tract is com- 

 paratively simple, but the nervous system shows a concentra- 

 tion of the postoesophageal ganglia similar to that described 

 for the Solifugse, except that a single pair of ganglia occurs 

 in the abominal region united by long connectives with the 

 cephalothoracic mass. Bight eyes are present, two of which 

 are larger than the others and situated at the anterior edge 

 of the dorsal surface of the cephalothorax, while the other 

 three pairs are situated laterally. 



The reproductive organs are paired and open by a median 



