SHIRAS EXPEDITIONS TO WHITEFISH POINT. 125 



for tlioy alone contained fish. The lieaeh ])()nds l)eIonging to creek 

 systems are of two kinds: (1) those of the lower beach, whicli are close 

 to Lake Superior and freel\' connected with it and (2) those of the older, 

 u])per. or fossil beach several hundred feet ])ack from the lake and with 

 scarcely any water connection with the lake except during s])ring; 

 floods. 



Lower Beach Ponds. Two of these were fountl in the region near ^'er- 

 milion, one at the mouth of Cranberry Creek (Station 31, Plate XVA) 

 and one a mile or so farther east on Wetherhog Creek (Station 121). 

 Fish might readily enter these ponds fioni Lake Superior, but there is 

 no evidence that they often do this. No fish were found on the lake 

 shoals anywhere near the mouths of these two streams, and the fauna 

 of these ponds is very different from that of Lake Superior. Each of 

 these ponds is long and narrow, extending several hundred feet making 

 a small angle with the lake margin. The water is stained brown but 

 free from sediment and has a variable temperature, usually' about 

 that of the air. They are shallow, under two feet in depth and the 

 bottom is of hard, yellow sand with conspicuous "ripple marks." 

 No vegetation except some diatom scum and filamentous green algae 

 Mas evident in the water and the shore was practically barren of veg- 

 etation. There were no noticeable water invertebrates, except a few 

 insects. Some aquatic beetles {Coptotomus intcrrogahis) were caught. 

 The following fish, given as near as possible in the order of their al)un- 

 dance, were found in these pools: common sucker, red-bellied dace, 

 Leuciscus neogacus, Cayuga minnow, silvery minnoAv, common perch, 

 horned dace, brook stickleback, Iowa darter, and brook trout. 



All of the fish taken in these pools are small examples of their species, 

 and none were represented in any numbers except the suckers, which 

 were only in a depression about two feet deep around a partly sub- 

 merged stump at Station 31. Here were a great man}^ little suckers 

 with very small examples of the other species listed, except the trout. 

 Only one trout was found and this was beneath a water-logged i)iece 

 of wreckage. Very few fish were moving out in the ojjen water of the 

 pond, but all staj'ed about objects which afforded some concealment. 



Upper Beach Ponds. The ponds of the upper beach are about two 

 miles west of Vermilion and are much larger than those just considered 

 and possess a larger biota. They are fed by Mason's Creek, and a 

 little, shallow, narrow outlet winds over the beach to Lake Superior. 

 The series of several ponds are not distinct from each other but are 

 expansions of one system. Two of. these are much larger than the 

 others and are about five hundred b\' seventy-five feet. Much vegeta- 

 tion is in and about these Ijodies of water, and this approaches in char- 

 acter that of the marsh lakes farther back from Lake Superior. At the 



