154 Lake Maxinkuckee, Physical and Biological Survey 



until it reaches the freezing point, varies directly with that of 

 the air, the water temperature will usually be close to freezing. 



In January, 1899, only 5 records were made (on the 1st, 8th, 

 29th, 30th, and 31st) , all of which were 32°. These were all taken 

 through the ice. In 1900, the variation was from 32° to 38° at 

 6 a.m., from 32° to 40° at noon, and from 32° to 39° at 6 p.m. 

 The lowest daily average was 32°, the highest was 39°, and the 

 average for the month was 33.8°, the average for the air for the 

 same period being 28.6°. 



In 1901, the variation was from 33° to 39.5° at 6 a.m., from 

 34° to 41° at noon, and from 33.5° to 40.6° at 6 p.m. The lowest 

 daily average was 33.7°, the highest was 42°, and the average for 

 the month was 36°, the average for the air for the same period 

 being 27.9°. 



In 1905, records were made only on the first 4 days of January. 

 The variation was from 32° to 34° at 6 a.m., from 32° to 34.9° 

 at noon, and from 32° to 34.8° at 6 p. m. The lowest daily average 

 was 32°, the highest was 34.3°, and the average for the 4 days 

 was 33.8°. 



Any discussion or interpretation of these January water tem- 

 peratures is difficult. Any consideration given them must be in 

 connection with the air temperatures. The observations in 1899 

 and 1900 were before the regular beginning of our work and were 

 made by a volunteer observer whose records must be regarded as 

 only approximately accurate. On all the days (9 in number) cov- 

 ered by records in January of those two years, the air was at or 

 below freezing, and on most of the days the water temperature 

 was taken through the ice. This will account for the large number 

 of records of 32° or slightly above. In January, 1901, the air was 

 at or below freezing on 24 days. The water temperatures were 

 taken perhaps with somewhat greater care. It is interesting and 

 significant to note, however, the close approximation of the aver- 

 ages for the Januarys of the 2 years, 33.8° in 1900 and 36° in 

 1901. 



Notwithstanding the almost freezing temperature of the water 

 near shore in January and other winter months, it was interesting 

 to observe that various species of small fishes such as grayback 

 minnows, straw-colored minnows, and skipjacks, gathered up in 

 large schools under the ice in shallow water, particularly on bright 

 sunny days. This phenomenon is considered more fully elsewhere. 



In February, 1899, only 7 records were made, on the 1st, 2d, 

 7th, 10th, 13th, 15th and 27th, on each of which dates the air was 



