28 MR. F. F. LAIDLAW ON 



<5 . Wings without any trace of colouring, even at the extreme 

 base. Pterostigmata black. 



Head : Lower and anterior surfaces entirely russet-brown. 

 Vertex a rich metallic blue. 



Prothorax brown. 



Thorax : Dorsal surface brown, its upper third with a metallic 

 green reflex. Sides also metallic green, with a brown band of 

 moderate width enclosing the stigma, continuous above with the 

 brown interalar sinus, and below with the brown colouring of the 

 under surface. 



Abdomen: Segments 1, 2, 3 a little dilated, as are 7, 8, 9, the 

 three latter each with a marked dorsal longitudinal keel ; 10 with 

 a similar keel, which is raised to form a well-marked projection 

 at the base of the segment. The abdomen is black, save for a 

 square yellow mark at the base of 7 on its dorsal side; this 

 yellow mark covers roughly the first quarter of the segment. 



1, 2, 3 have a distinct metallic-green lustre, which fades 

 gradually and disappears almost entirely on 4. 



The legs are long and entirely black. 



Anal apjjendages (text-fig. 2) black, the lower one longer than 

 the upper pair and distinctly bituberculate at its extremity, and 



Text-figure 2. 



Anal appendages of Macromia euterpe. 



with a slight upward curve. The upper pair each carry a very 

 small tooth on their outer margin at the middle of their length. 

 This tooth is so small that it may be spoken of as " obsolescent." 



The female in colouring scarcely differs from the male ; the 

 bases of the wings have a very faint smoky-yellow tinge. 



The abdomen is, on the whole, stouter than in the male, and 

 consequently segments 2, 3 and 7, 8, 9 not so markedly dilated. 



The types <3 $ will be deposited in the British Museum. 

 Co-types <$ $ bi Sarawak Museum and <5 in my collection. 



In general, this species approaches M. tvestivoodi Selys. I 

 have some doubt as to whether the male from Banka described 

 by Selys in the 2 me Addit. au Synops. Cord, is really co-specific 

 with the female which is the type of the species. In any case 

 the male of 31. euterpe differs from that male in details of 

 venation, in the position of the boss on segment 10, and in the 



