732 Deraoll, Gelegentliche Beobachtungen an Libellen. 



vidual appears to have a domain, as it were, of its own. West- 

 wood tells us that he has seen what he believed to be the same 

 individual hawking daily for several weeks together over a small 

 pond. The writer observed a specimen of Cordulegaster annulatus 

 to frequent a particular bush, to which it returned - - frequently to 

 the same leaf --after an excursion in search of food. The way in 

 which these Insects actually seize their prey has not yet been made 

 clear; it is certain that they capture flying Insects, and it seems 

 most probable, as we have already said, that this is done by means 

 of the legs. These, as we have said, are inserted so as to be 

 very near to the mouth: they are directed forwards, and are held 

 bent at right angles so as to form a sort of net, and are armed 

 with a beautiful system of fine spines: it is probable that if the 

 dragon-fly pursue an Insect on the wing and strike it with the trap, 

 formed by its six legs, then these immediately come together under 

 the mouth, so that the victim, directly it is captured by the leg- 

 trap of its pursuer, finds itself in the jaws of its destroyer. It is 

 perhaps impossible to verify this by actual observation, as the act 

 of capture and transfer is so very brief and is performt in the midst 

 of a rapid dash of flight, but it seems more probable that the 

 prey is first struck by the legs than that the mouth is the primary 

 instrument of capture. The excessive mobility of the head permits 

 the victim to be instantly secured by the mouth, and the captured 

 fly is turned about by this and the front pair of legs, and is nipped 

 rapidly so that the wings and drier parts fall off; the more juicy 

 parts of the prey are speedily squeezed into a little ball, which is 

 then swallowed, or perhaps we should rather say that the mouth 

 closes on it, and submits it to further pressure for the extraction 

 of the juices." 



. Ob die Tiere in der Luft die Beute mit alien Beinen ergreifen, 

 konnte ich nicht feststellen. Doch scheint es mir nichtsehr wahrschein- 

 lich, da ich vermuten muss, dass die Tiere die Beute von unten 

 anfliegen. Ob beim Festhalten die drei Beinpaare in Tiitigkeit 

 sind, kann ich auch nicht angeben. Doch habe ich me beobachtet, 

 dass die Tiere beim Zuruckkehren nach ihrem Standort die Beute 

 mit alien Beinpaaren gehalten hatten. Stets sah ich schon bevor 

 sie sich niedersetzten, die beiden hinteren Beinpaare frei. Kleine 

 Tiere wurden nur mit den Mundwerkzeugen gehalten, grofiere von 

 diesen und dem ersten Beinpaar. 



Es findet eine sehr vveitgehende Zerkleinerung statt (Jor- 

 dan, 1913, I. Bd. Jena.) Die Oberlippe, die Mandibeln, die ver- 

 breitcrten Taster der Unterlippe (nach anderen die Aufienladen 

 derselben), und die Aufien- und Innenladen derselben arbeiten alle 

 synchron gegeneinander. Die ersten Maxillen konnte ich nicht zu 

 Gesicht bekomrnen. Kleinere Tiere werden vollstandig verzehrt. 

 Bei etwas grofieren werden wahrend des Zerkauens grofiere Chitin- 

 stiicke, die von alien Weichteilen befreit sind, wieder nach aufien 

 befordert. Bei noch umfangreicheren Beutetieren werden erst die 

 Fliigel und Beine entfernt, und zwar in der Weise. dass der 



