. Brimleyana. Zoology; Ecology; Natural history. Jellyfish 39 lection site, a significant difference (Kruskal-Wallis ANOVA on Ranks; H = , P < ). Among sites outside the swarm location, there was also a trend of increasing size with distance from the swarm; mean medusa diameter was largest 350 m from the swarm, the location at which medusae were first observed when entering Wolf Fork from the reservoir. Within the swarm there was a bimodal size distribution of medusae concentrated in 9 - 13 mm and 15-18 mm size classes, with more medusae in the smaller size classes. Away from the sw
. Brimleyana. Zoology; Ecology; Natural history. Jellyfish 39 lection site, a significant difference (Kruskal-Wallis ANOVA on Ranks; H = , P < ). Among sites outside the swarm location, there was also a trend of increasing size with distance from the swarm; mean medusa diameter was largest 350 m from the swarm, the location at which medusae were first observed when entering Wolf Fork from the reservoir. Within the swarm there was a bimodal size distribution of medusae concentrated in 9 - 13 mm and 15-18 mm size classes, with more medusae in the smaller size classes. Away from the swarm most medusae were in the larger size classes, but a semblance of the bimodal pattern was apparent (Fig. 2). Fig. 3 Size distribution of C. sowerbyi medusae collected 0 and 100 m from a dense concentration (swarm) of medusa at Wolf Fork, Stonewall Jackson Lake, West Virginia on 18 August and 12 September 1995. Otherwise as for Fig. 2. 18 August 1995. 4 6 8 10 12 14 16 18 20 22 4 6 8 10 12 14 16 18 20 22 Medusa diameter (mm) On September 12, I observed fewer medusae than on previous visits to Wolf Fork. Water temperature was 25 C, and reservoir level had dropped about 1 m since the previous visit. The sky was overcast and light rain was falling, whereas the sun shone on previous visits. Medusae were most abundant near the 18 August swarm site; at 100 m they were scarce, and were not observed else- where. Mean diameter of medusae was the same at both locations (Fig. 3), although more medusae from the 100 m site were in the largest size classes (20- 21 mm). Between August 18 and September 12, mean diameter of medusae at the swarm location increased slightly more than 4 mm (Fig. 3). This is equiva-. 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 original North Carolina State Museum of Natural History. [Raleigh, NC :
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