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Habits. — This species is diurnal and thoroughly 

 aquatic during its period of activity, being found in 

 small ponds or pools or among the grass on the 

 borders. It is very agile in the water, and proceeds 

 by small leaps on land. It likes to rest near the 

 surface of the water with spread-out limbs, nothing 

 but the eyes and nose emerging, and dives to con- 

 ceal itself in holes or under stones or bury in the 

 mud when disturbed. I found it pairing near Berlin 

 in the latter half of May. The male embraces the 

 female round the waist, and, swelling out its throat, 

 utters at short intervals a somewhat powerful and 

 melancholy note, liooh, hook, or hoonh, hoonh, whence 

 the name " Unke " by which it is generally known in 

 Germany. The pairing season extends over two or 

 three months, and Heron-Royer has ascertained that the 

 female spawns two or three times in the year at distant 

 intervals. The eggs are produced singly or a few at 

 a time, and become fixed by their gelatinous capsules 

 to submerged grass or other weeds ; this operation is 

 performed slowly, and may last from one to three 

 days, with several hours' interruption. 



Males appear to reach sexual maturity much sooner 

 than females. I have found pairing male specimens 

 not more than 2S mm. long from snout to vent, 

 although the young that have just completed the 

 metamorphosis measure as much as 15 to 20. 



