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THE AMEBIC AN NATURALIST [Vol. XLIV 



spawn by A. jeffersonianum precedes that by A. puncta- 

 tum by a few days. It has been impossible to visit daily 

 the pools where the spawn of A. jeffersonianum is most 

 abundant, owing to their distance from the university; 

 one pool much nearer has yielded a small amount of it 

 and has provided more accurate although more scanty 

 data. In general the deposition of the bulk of the jef- 

 fersonianum spawn coincides with that of the first punc- 

 tatum spawn. Variations from this occur — for instance, 

 this year the spawn in the single pool just mentioned 

 followed the above rule, while in the group of four pools 

 nearly all the jeffersonianum spawn had been deposited 

 three days before any punctata >n spawn appeared; and 

 to complete the irregularity the last spawn of all to be 

 deposited was that of A. jeffersonianum. It was in 

 small quantity and probably all from one female. 

 (These eggs and the larvae from them were unusually 

 small, the larva* seemed vigorous, but could not be kept 

 alive many days after their own supply of yolk was ex- 

 hausted.) Another check on the time is furnished by 

 the spawning of liana sulvatica. This year — an un- 

 usually early season — the writer observed the first 

 deposition of spawn in these pools by the wood-frog. It 

 began at 10.30 a.m., March 31. Spawn of A. jefferson- 

 ianum had appeared seven days previously. 



4. Spawn-masses.— The typical spawn mass of A. 

 jeffersonianum is a small one, the number of eggs being 

 usually about twenty; the extremes encountered have 

 been small masses of jelly without any eggs and a mass 

 containing forty-one. A. punctatum does indeed deposit 

 masses of spawn containing as few eggs as this, but the 

 number is usually much larger. The complement of 

 ripe ovarian eggs carried by two females of average 

 size was 128 and 161. These are probably representa- 

 tive numbers and indicate a rather smaller complement 

 than that possessed by A. punctatum— 130 to 225— 

 (Wright and Allen, 1908) which in turn is much smaller 



5. Hardly less characteristic than the small masses is 



