1909] 



227 



ON THE OCCURRENCE OF 

 SOMATOCHLORA METALLICA, Van dee Lind., IN SUSSEX. 



BY E. K. SPEYEE, F.E.S. 



Somatochlora metnllicf, Van der Lind., is a dragon-fly belonging 

 to the Sub-family CorduJiince, which forms a link between the Libel- 

 lulince and the ^^schnincs, and contains four British representatives 

 in all. The Corduliiue commonly found iu the South of Enghmd is 

 Gordiolia cenca, Linn., and this being an insect with which the present 

 one might possibly be confused, a figure of the male anal appendages 

 of S. metallica is here given. The most important difference between 

 them lies in the form of the lower anal ap- 

 pendages, which m Somatochlora nve triangular 

 and undivided, but are deeply bifid in CorduUa 

 cenea. In its congener, S. arctica,7iett.,ihit lower 

 appendages are also undivided, but instead 

 of two, there are three teeth on the ventral 

 side of each of the upper appendages, which, 

 in addition to beirjg longer in proportion 

 than those of <S'. metallica, are curved inwards 

 at their extremities as well as in the middle. 

 No difficulty should be experienced with the 

 identification of the remaining species, Oxy- 

 ffttstra curtisii, Dale, as it is characterised by 

 longitudinal yellow spots in the median line 

 of the abdomen, and a long spine on the 

 ventral surface of the upper appendage. 



The extra- British distribution of S. metal- 

 lica is a wide one, and from the various 

 sources of information available, I have brought together records 

 showing its occurrence from Lapland and Scandinavia on the north 

 to Italy on the south ; on the west from France and Belgium, through 

 Switzerland, Germany, Austria to European Eussia on the east, and 

 it is even believed to occur in Northern Siberia. 



Regarding the Continent as a whole, the period of flight seems 

 to extend from about the beginning of May to the end of August. 

 De Selys gives May 10th— July 20th as the period of flight in 

 Belgium (Revue des Odonates, 1850) ; Zetterstedt records it near 

 Lund in Sweden on May 16tb (Insecta Lapponia, 1838), and Brauer 

 from May to August in Austria (Neuroptera Austriaca, 1857). Hagen 

 says it was very common at Konigsberg in June (Synonymia Libellu- 



Anal appendages of Somatochlora 

 metallica, Van der Lind., seen 



from above. 

 Drawn irom a Sussex specimen. 



