30 Bulletin Wisconsin Natural History Society [Vol. 11, Nos. 1-2 
forms were doubtless present in the sand (Warming ’09, p. 175). 
Six zones were distinguishable as follows (fig. 26) : 
1. The line of drift at the highest mark left by the water. Here 
the “beach-combers” Orchestia, Talorchestia, spiders, flies and 
beetles were found. 
2. The gently sloping beach below was partly covered at high 
tide. Its only inhabitants were the two burrowing semiterres- 
trial amphipods, Orchestia and Talorchestia, and the agile tiger 
beetles. 
3. Chiridotea swarmed on the rather flat ripple-marked beach 
nearer the ocean, and in the little puddles at this level a few 
Littorina litorea clung to the firm sand. 
4. On the compact arched beach just below Chirodotea was not 
so common. Here Polineces made its appearance, though no indi- 
viduals were as large as those in Zone 6 (fig. 26). 
1 
Fig. 26. A Sectional View of the Sand Beach at Station 4 (Fig. 1.) 
Showing the Zones. 
5. The rapid slope of this beach did not permit sand to collect; 
it consisted of pebbles, stones, and shells. No animals were seen. 
6. The gently sloping expanse of sand that could be followed 
for more than a hundred feet by wading at low tide gradually 
descended into deeper water. Its fauna was more varied than 
that of any of the zones above. On its ripple marked surface 
Polineces was common and often attained a length of four inches. 
Pagurus acadianus (often bearing Hy dr actinia, Spirorbis, or Cre- 
pridula), Crago, and Cancer irroratus wandered over the surface 
of th‘e sand. The Cragos captured were all adult females carry- 
ing eggs. In the shallow water Idothea baltica, Calliopus, 
Gammarus anmdatus, and fish hunted for food. These animals 
migrated to higher levels with the rising tide. Burrowing in the 
sand were found : Polineces, Nephthys, Echinarachnius, and Venus. 
Cyanea was often stranded on the beach or pulsated slowly in 
the shallow water. 
