NATURAL HISTORY OF AMIA CALVA LINNAEUS: 97 



The male then moved away a short distance, and as he did so the third sub-school, 

 now drawn out into a long straggling train, which followed along the earlier trail of 

 the male, also joined him and the train shortened. Thus all the parts of the school 

 were reunited into a single body." 



The accompanying sketch made at the time illustrates accurately the move- 

 ments of another school after the male had been frightened away. This swarm was 

 among hummocks (dotted areas) and bunches of grass (lined areas), and when the 

 observation began was at A. Its subsequent movements, its subdivisions, and the 

 frequent returns to the point B, where, without much doubt, either the school or 

 the male had been for some time previously, and its final reunion with the male 

 when, after fifteen minutes, he returned to the point C, may all be followed in 

 the figure. These larvae were about 20 millimetres long. 



The rate at which the schools move increases greatly with the age of the larvae 

 and doubtless also at any age with the conditions, such as abundance of food. In 

 a school of larvae of about 20 millimetres I have noted a rate of about 16 metres per 

 hour. In another case I have found a school of larvae of about the same size within 



5 metres of the spot on which it was five hours earlier, another within 12 metres of 

 its original location, and another within 30 metres. 



By learning to recognize the individual males I have been able to find certain 

 schools from day to day and thus to learn something of their daily wanderings. 

 Connected by a narrow channel with the Geddes mill-pond on which the camp of 

 1901 was located is a small basin of about two acres extent. The Amia nest here. 

 On May 10 four schools of larvae could be identified in this basin. These from the 

 peculiarities of the males, previously noted, I have called the "split-tail," the "deep- 

 split-tail," the "brush," and the "two-spot" schools. I was able to find these nearly 

 every day for eleven days, that is, until May 20. The " deep-split-tail " school occu- 

 pied a little bay running off from the basin and not more than 2 metres wide and 



6 metres long. Here it was found on six different days up to and including May 

 18, and was still in the basin on May 20. Of the other schools one occupied the east 

 side and one the west side of the basin, and a third frequented the bushes on the 

 north side. They were usually to be found daily in these localities up to May 20; 

 if not found in their usual places, it was because they were temporarily in the centre 

 of the basin. On May 20 the larvae were 30 to 32 millimetres long, the size at which 

 the brighter colors begin to appear. After this, although one of the schools was 

 found in the basin nearly every day until June 16, it was no longer possible to find 

 them all, and after May 30 only one school could be found. On account of the in- 

 creased wariness of the male, the more rapid movement of the school and its habit 



