530 IV AR TRÂGARDH 



the form usual in Eugamasus, Pergam.asus and ParasiUis, 

 the médian mucro, which is of even width in the basai half, 

 narrowing abruptly in the middle, and rounded at the top. The 

 latéral cusps are onl}^ one third of the médian one, only slightly 

 longer than they are wide at the base, and finely pointed, with 

 even edges. 



The only species whose epistoma resembles itto a certain 

 extent is Parasitus consanguineus Oudms (Berlese 1906, 

 PI. 15, fig. 10). 



Mandibles (fig. 19) of the type found in P. fucorum (De Geer). 

 E. trouessarti and others, in which the top of the upper jaw 

 points straight forwards, and there is a larger, perpendicular, 

 subterminal tooth, two features which give to the end of the 

 jaw a striking resemblance to a fish-tail. 



Lower jaw considérably shorter than upper one (4 : 5) ; 

 it is of almost uniform width for the greater part of its length, 

 and curved at a right angle at the top ; terminal tooth projecting 

 when the jaws are closed, to the middle of the height of the 

 upper jaw ; behind the terminal tooth the edge is convex 

 for a short distance, médian tooth placed a little beyond the 

 middle, poingting slightly backwards ; behind this, the edge is 

 even and straight. Calcar mandibuli of almost even width 

 throughout, fused with the lower jaw in front of the médian 

 tooth ; its ventral edge forms an unbroken Une with that of 

 the jaw in front of the point where they are fused ; it bends 

 in an even curve downwards, the top of the curve being in the 

 basai third, and forms a comparatively broad fissure with the 

 lower jaw, almost as wide as the calcar itself. 



Upper jaw tapers very slowly towards a level with the lower 

 termial tooth, where it has a deep semicircular, ventral inci- 

 sion, and where it bends slightly downwards. Dorsal edge 

 slightly concave in the proximal half, slowly rising on to a level 

 with the lower terminal tooth, where it again bends downwards, 

 with slightly concave edge, having thus the appearance of 

 being gibbous or hunchbacked. Terminal tooth rounded at the 



