BY R. J. TILLYAHD. 413 



other dragonflies, particularly the large hawk-like Hemicor- 

 dulia tau, which will hover over them and every now and 

 again swoop down and try to knock them into the water. 

 At other times males of their own species will come and attack 

 them viciously, and sometimes this will lead to a tussle between 

 the two males for the possession of the female. If uninterrupted, 

 and settled into a satisfactory position, the pair will remain 

 motionless for a short time; then the female also arches her 

 abdomen, dipping just the tip of it into the water and pressing 

 it against the stem on which they are resting. In this way the 

 ova are laid. On dissecting a fertile female I found that the 

 ova lie longitudinally along the ventral portion of the abdomen, 

 often reaching as high up as the third or fourth segment. They 

 appear to be exuded only one at a time. In coming into contact 

 with the water, the sticky substance which holds them together 

 dissolves immediately and they fall down into the water. I am 

 forced to this conclusion, although from the action of the female 

 in pressing her abdomen against the stem or stalk, one would 

 naturally suppose that the ova were deposited either on the stem 

 or possibly inside it. Several times I spent many hours in 

 collecting the leaves and stems of reeds and water-plants on 

 which I had plainly seen Lestes leda ovipositing the moment 

 before, but never once did I find any ova. Sometimes the stem 

 would be hollow, and in this case I fancied the ova might have 

 been inserted into it, especially from their shape, and because 

 the female has a habit of working down a stem a short distance 

 at a time, apparently placing her eggs in order. But the inside 

 of these hollow stems never revealed any ova; besides which the 

 ovipositor in Lestes is not particularly sharp, as it is in some other 

 genera, such as Argiolestes. From experiments I have made with 

 the larger species of other families of the Odonata, it appears 

 that the gum which holds together their egg-clusters is imme- 

 diately soluble in water if it does not come into contact with the 

 air first. That this is also the case with Lestes leda there can be 

 little doubt; and if so, the ova must fall at once to the bottom of 

 the pool, the female only using the stem for pressure. 



