ARKIV FÖR ZOOLOGI. BAND 6. NiO 2. 



Diagiiosis of Speleorchestes. 



Body elongate, abdomen long and sackshaped, witli two 

 distinct, transverse furrows in the anterior half. Cephalo- 

 thorax distinctly separated from abdomen, short and narrow, 

 anteriorly truncate, with two pairs of long slender, pectinate 

 sense hairs and tbree pairs of plumose bairs. One pair of 

 small, biit promiment eyes. Rostrum Jarge and conical, as long 

 as, or longer tban cephalotborax. Mandibles large, cbelate, 

 witb a portion proximally at tbe median side detacbed as a 

 peculiar pear-sbaped structure. Palps 5-jointed, witb large 

 2nd joint, 1st, 3rd and 4tb joints very sbort, terminal joint 

 broad at tbe top and divided into 3 — 4 sbort tubercles witb 

 one pointed bair eacb. Body bairs densly bairy, obtuse at 

 tbe top and accumulated at tbe posterior end of abdomen. 

 Legs 1 — 3 5-jointed; legs IV 6-jointed. One claw. 



From tbe diagnosis given above it may be seen at 

 tbe present genus differs from Nanorchestes in tbe following 

 respects. 



Speleorchestes Nanorchestes 



Palps 5-jointed; 5tb joint > Palps 4-jointed; 2 > 3 > 4; ter- 



3 + 4; terminal joint 3 — 4- minal joint witb crateri- 



lobated witb long bairs. formpapilla,surroundedby 



small, cirriform bairs. 

 Mandibles large, cbelate. Mandibles bttle developed, 



sbaped as in Eyre7ietes, 



consequently not cbelate. 



Body elongate; sboulders not Body squarebuilt, sboulders 



projecting. large and projecting as in 



Tromhidium holosericeum. 



Tbe present genus is in several respects very interesting. 

 Its features will be discussed more fully after tbe descrip- 

 tions of tbe two species, but I can not omit pointing out 

 bere, bow extraordinary it seems on first tbougbt tbat one 

 species lives in wbite ants nests in Soutb Africa, tbe other 

 in ants nests in Sweden. Evidently it enjoies a very wide 

 distribution and tbe fact tbat it bas up to tbe present time 

 escaped tbe acaridologists is explained only by its subter- 



