39 34 Proceedings of the Royal Irish Academy. 



the median line furnished with a transparent, long and narrow lesser appendage, 

 which at its end is somewhat broader and roughly truncated [petiolus]. On 

 each side of this proceeds another appendage, which is erescentic and tolerably 

 broad [club-shaped organs] ; these two meet at their ends outside the median 

 lying appendage. On each side of this [pair] are two long hairs, twice the 

 length of the appendage. Examining the creature from the upper side, there 

 appears (as in A. tricuspidator and A. emarginator) above this appendage 

 in the median line another short appendage, of equal length and breadth, 

 transparent, furnished at its hinder end with two incurvations; upon this at 

 each side stands a short knob, and at the apex a long hair [hyaline-appendage]. 

 The ' impressed line ' is posteriorly invisible, and more obscure than in other 

 species within the genus ; the part of the back included is inconsiderable. The 

 epimeral groups are divided by a very inconsiderable interval, the inner ends 

 of the fourth pair almost touching each other. These epimera are nearly 

 square, more than twice the breadth of the third pair. Labium short and 

 broad, rounded semicircularly behind. Anus situated and shaped as in the 

 last species [A. papillator Miiller], but without the enclosing elevations. 

 In colour it is bright green, somewhat approaching to yellow, with two 

 inconspicuous brown patches on the back. Under side, legs and palpi yellow- 

 green." 



The length of the Irish species is about 1*2 mm., breadth '88 mm. The 

 colour is yellow tinged with green, with reddish brown markings, and the legs, 

 palps, and epimera are pale green. 



The body (PI. III., fig. 26 a) is oval in shape, hinder end suddenly con- 

 tracted and produced to form a well-defined appendage. The dorsal groove 

 encloses rather less than half of the upper surface ; it is evenly rounded in 

 front, sinuate at the sides, and ends on the side margins of the appendage. 

 The hyaline-appendage, the petiolus, and the enclosing club-shaped organs 

 (PI. III., fig. 26 b) appear to agree closely with those of A. nobilis. In 

 A, Kanei, however, there is a blade-like chitinous process on each side of the 

 hyaline-appendage which is not indicated by Neuman in his description or 

 figure of the Swedish species. The petiolus and club-shaped organs spring 

 from a rounded prominence on the underside of the body appendage. The 

 epimera are extremely large, fourth pair quadrate approaching quite close to 

 the genital area. 



The legs are long and robust, and the spur on the fourth segment of the 

 last pair is very strongly developed. 



The palps (PI. III., fig. 26 c) are short and stout ; the inner end margin of 

 the second segment is curved outwards and carries about three moderately 

 long hairs ; on its dorsal surface are three or four bristles, one of which is 



