Introduction. 7 



times eat one another cannot be denied, for the writer 

 has more than once caught a large Dragonfly in 

 possession of one of its smaller brethren, and on one 

 occasion watched — indeed, was the cause of — a striking 

 piece of cannibalism.'^ There fell to the net a male 

 Anax iuiperator, which had just before captured a Syni- 

 petruni scoticiini — the small black Dragonfly. This it 

 almost killed, but released in the net. While iinpcrator 

 was held b}' the wings, another scoticuni was ofiered, 

 which it seized with its legs, but after biting let fall 

 also. On scoticHin being offered a second time howex'er, 

 all except the wings and part of the abdomen was 

 quickly devoured with e\ident pleasure. It should be 

 mentioned that scoticuni, being but just on the wing, was 

 soft and tender. On another occasion a Lihcllula 

 quadriniaculata was secured eating an example of the 

 crimson Dragonfl\-, PyrrJunonia nynip/iula\\ and Mr. 

 \V. J. Ashdown mentions the fact of his having taken 

 in the New Forest a specimen of Gonphus vulgatissinius 

 also making a meal off an individual of the same small 

 species. Some large insects, probably a species of Asilus, 

 have been noticed preying on Dragonflies in California.:]: 

 Coming to smaller foes, acari, or tiny red spider- 

 mites, are sometimes found as external parasites, and 

 are occasionally so closely packed on parts of the wings 

 as to mark them with red. The genus Synipetruni seems 

 to be most commonly attacked, and in S. nicridionalc 

 they are said to be almost looked upon as a specific 

 character.§ What nutriment they can extract from a 



* Entom., i«97, p. 281. t Entom., 1897, p. t,^. 



\ R. McLachlan, Entom., 1873, p. 549. 



§ R. McLachlan, E. M. AI., 1864, p. 100; id. 1884, p. 252. C. A. 



Briggs, iJ. 1892, p. 194. 



