Clare Island Survey — Acarinida. 



39 39 



West — continued. 



*Atractides aniplexus Koenike. 

 Atrac tides brevirostris nov. sp. 

 Unionicola rivularis nov. sp. 

 Wettina podagrica (C. L. Koch). 

 Piona paucipora (Sig. Thor). 

 Arrhenurus Kanei Halbt. 

 Arrhenurus Stecki Koenike. 

 Arrhenurus Neumani Picrsig. 



East — continued, 



Forelia parmata Koenike. 

 *Aturus intermedins Protz. 1 

 Arrhenurus mediorotuudatus S. T. 

 Arrhenurus Freemani Halbt. 

 Arrhenurus affinis Kocn ih . 

 Arrhenurus battilifer var. dilatatus' 

 Arrhenurus truncatellus (0. F. M. ). 

 Arrhenurus bipapillosus nov. sp? 



1 In the River Liffey at Blessingtou, county Wicklow. 



2 Differs from the typical form chiefly in the shape of the petiolus, which is a little shorter and 

 is distinctly swollen on each side beyond the middle. Seen from above the ends of the genital plates 

 do not project beyond the sides of the body appendage as they do in the typical form (8) sent to me 

 by Dr. Koenike. Found in old ponds at Raheny and Sutton, county Dublin (Plate III., fig. 23 a-c) (5). 



3 Arrhenurus bipapillosus nov. sp. Male : — Length '72 mm., breadth -61 mm. Colour yellow 

 with brown markings, and paler coecal area. Outline of the body rounded in front and slightly 

 flattened on the sides. At a point a little in front of the posterior third it is gradually narrowed 

 towards the body appendage. The latter is rather small, and its sides are almost continuous with those 

 of the main body. The apex of the appendage is truncated and distinctly indented (depth about 

 ■033 mm.) at the centre somewhat as in the American species A. ovalis Marshall. On each side of 

 this central notch there is a small hyaline papilla and close to this a long straight hair. Near the 

 base of the upper side of the appendage there is a curious wedge-shaped petiolus (Plate III., fig. 23 4), 

 and on each side of this there is a stout bristle of moderate length which is curved outwards at the 

 extremity. The third and fourth epimera are narrow and of great breadth, their inner ends separated 

 by a very slight interval. Capitular recess very wide. The genital plates are deep at their bases, 

 and narrow rapidly towards the sides of the body, which they do not overreach. Inner face of the 

 second palp segment with a small group of rather long pectinated spines ; fourth segment narrowed 

 towards the extremity (Plate III., fig. 23c). 



Locality: Found amongst weeds dredged from the Grand Canal near Clondalkin, county Dublin, 

 by Miss J". Stephens, in October, 1908. 



