Frog spawn of the common frog, Rana temporaria, deposited in a small pond in late March early April. The coupling of frogs, called amplexus, involves the male instightly cuddlingins the female until she expels her eggs. The male then fertilizes them. When the spawn is first depoisted it is in a tight mass the size of a golf-ball. It swells rapidly in the water until it reaches the size of a coconut and floats on the surface. The nuclei of the eggs divide to form embryos. These develop until tiny tadpoles emerge to feed on the jelly. Eventually they free themselves from the jelly, swim off and continue to feed on algal growth.