100 Notes on the Frog. [Sess. 
resolved to prove to my own satisfaction, if possible, whether 
they ate each other or not. There were thirteen ova in the 
tube, and these I put in a large basin holding about four 
gallons of water. In the basin I placed a pot in which grew 
several aquatic plants. I also threw in some duckweed, which 
floated on the surface of the water, and set the basin in a green- 
house exposed to the light and sunshine. Here twelve of the 
ova hatched, and several times each day I carefully noted 
their movements, changes, &c. In a week they were hatched, 
although they did not leave the gelatinous mass that sur- 
rounded the ova until it was all consumed, which took about 
eight days. I considered they were hatched when the tad- 
poles straightened out. For four or five days or longer, 
although seemingly perfectly formed, they remained rolled up 
like a scroll. After leaving the thin, almost invisible, fibrous 
material that seemed to hold the spawn mass together, there 
was easily seen a very small branched opening on each side 
near the head, which nearly in every case disappeared in from 
two to four days. After they began to swim about, until the 
head—or to be exact, the body, as there is no distinct head— 
got round or tumid, they almost constantly kept in groups 
when feeding, which at the first was always upon the stalks 
of the plants. Very often there was a line of six or eight, 
almost touching one another, along the one side of a branch 
of Ranunculus aquatilis, where they would stick for hours 
at a time, as if pinned by the head to the plant. After the 
body got plump, however, they became more lively, and : 
moved about more, seemed more independent of each other's 
company, and never fed long at a time without shifting 
their position. They now began to feed more upon the x) 
confervoid growth which covered the sides of the flower-pot 
and basin. 
It was now, after they had been nearly four weeks swimming 
about, that I thought of trying them with some special food. 
I dropped into the basin one or two small caterpillars first, 
which they paid no attention to. Then I tried some small 
worms. They now evinced a little interest, but upon the worms 
making the slightest move they were off as fast as they could — 
swim. All along they were very shy and timid, the slightest 
shake, or the passing of the hand over the basin, sending them © 
