AQUATIC INVERTEBRATE FAUNA OF WYOMING AND MONTANA. 209 



snows on its upper slopes. The situation here is one of the most attractive in the 

 Park. Camping ground and feed are good, water is abundant and excellent, fish of 

 three kinds trout, chub, and sucker are plenty in the lake, and minnows can be 

 taken by the half bushel in the warm waters of Witch Creek. The place is absolutely 

 retired (there was not even a trail by the way we came) and quite off any line of travel 

 even proposed by the Park authorities. The lake is a gem of beauty, a fit companion 

 to the noble mountain, from whose heights a view of lakes and rivers and mountain 

 peaks and ranges may be had second to none in this part of the Rocky Mountains. 



Our stay in this charming spot extended to nearly five days, all of which but one 

 were spent in continuous collecting from the lake and from the tributary already men- 

 tioned as Witch Creek. Violent winds made it difficult to work far from shore in our 

 light canvas boat, but, with the aid of a small raft made for the occasion, we got good 

 soundings and dredged successfully about a quarter of a mile out. Here, besides the 

 kinds of collecting already specified, we used our small seine in Witch Creek and the 

 trammel net in the lake, taking in the latter considerable quantities of all the larger 

 kinds of fish the lake supports, in places where the rocky bottom would have made 

 seining impossible even with a much more cumbrous apparatus. 



We shifted camp on July 31 to the west bay of Yellowstone Lake, passing Rid- 

 dle Lake on our way and pitching our tents on the shore, a few rods above the Upper 

 Geyser Basin of this bay. Here a line of soundings was run out about 2,000 feet, 

 the dredge was hauled from the boat 1,000 feet from shore at a depth of 102 feet, 

 with a bottom temperature of 46, and at various lesser depths near shore. Other 

 collections were made from the lake in the usual variety, and also from several of 

 the warm springs and their outlets. The first water birds were shot here for a 

 study (by Prof. Linton) of the relations of the fish-eating birds to the parasitism of 

 the trout, and descriptions were made of rotifers and protozoa which it was not 

 possible to preserve for later study. A short excursion from this camp gave us 

 access with the boat and our lighter apparatus to Duck Lake, a land-locked body of 

 water, formerly connected with Yellowstone Lake, but having now neither inlet nor 

 outlet at any season of the year. At the foot of Yellpwstone Lake, where we arrived 

 August 5, our party was reorganized by the dismissal of the guide and pack train and 

 the engagement of a teamster and saddle horses for the remainder of the trip. 



From this point we worked on the lower lake, on Yellowstone River at the outlet, 

 and on Pelican Creek and smaller tributaries, until the 12th of August, Prof. Linton 

 going for pelican to the head of the lake, in a skiff, on the 9th and 10th, with a.volun- 

 teer party from the lake hotel. Towing-net collections were made by this party not 

 far from the inlet. The dredge was run from a skiff off the landing, on this visit, at 

 a depth of 100 feet, and also in shallower water. Being unable to reach deeper 

 water for want of a line left at Norris Geyser Basin, and needing also other supplies 

 left there, for which I was unable to get transportation to the lake, we left the lake 

 for a time, starting to Norris Basin on the 12th. The 13th was spent at the Trout 

 Creek camp, collecting in waters of various temperatures from Alum Creek, above 

 and below the remarkable hot-spring basin through which this stream flows. 



The occurrence of small trout in the upper course of this little creek seemed at 



first a mystery, since they are found above the hot springs which boil up in its bed 



for a distance of several rods, and so make its waters there altogether intolerable to 



fish; but it finally appeared that when the streams are filled by melting snow in 



F. C. 13. 1891 14 



