. Bulletin - New York State Museum. Science. 230 NEW YORK STATE MUSEUM and remains stopped till the pools are refilled in late autumn, and the stems and leaves, now dead, fall into the water. I have gathered the eggs in the middle of July and again in the middle of October and found them at apparently the same stage of de- velopment. Eggs placed at the latter date in a. bowl of water in my laboratory hatched within a week. I did not try hatching any of them earlier. Exposed as they are above the water, these eggs are subject to parasites, which destroy often a large proportion of them. From a
. Bulletin - New York State Museum. Science. 230 NEW YORK STATE MUSEUM and remains stopped till the pools are refilled in late autumn, and the stems and leaves, now dead, fall into the water. I have gathered the eggs in the middle of July and again in the middle of October and found them at apparently the same stage of de- velopment. Eggs placed at the latter date in a. bowl of water in my laboratory hatched within a week. I did not try hatching any of them earlier. Exposed as they are above the water, these eggs are subject to parasites, which destroy often a large proportion of them. From a handful of bur reed leaves well studded with Lestes eggs, Fig-. 6 The egg- of Lestes uncati. I once bred large numbers of the following parasites, the two last named being hyperparasites on the third named in the list. Brachista pallida Ashm. Centrobia odonatae Ashm. Polynema needhami Ashm. Tetrastichus polynemae Ashm. Hyperteles polynemae Ashm. The nymphs live among submerged plant stems. Their ex- tremely slender legs, long swaying bodies, and leaflike gill plates, together with a sober color pattern of greens and browns, render them very inconspicuous when in their native haunts. In aquariums they are rather shy, and do not feed under observa- tion so readily as do many other genera. I have observed them eating some of the larger entomostraca and smaller dipterous larvae (Corethra and Chironomus). Since the nine species occurring in or regional in New York State have all been described several times in recent and avail- able papers, and since the females are well nigh indistinguish- able, and determinations must at present be based on the males and chiefly on the form of the terminal abdominal appendages of the males, I have not thought it worth while to give descrip-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the orig
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