Tino Florez, age 13, of Visalia, Cali .the question:

What kind of mammals lay eggs?

There was a time in the dim distant past when many ancestors of our mammals laid eggs. But so far as we know, there are only two mammals in the modern world that lay eggs. One is the echidna and the other is the duckbill platypus. Both of them are natives of Austrailia and the echidna is found also in New Guinea.

The echidna, alias the spiney anteater and the hedgehog, may be fifteen to 30 inches in length   depending upon the kind of echidna he is. His coat is an amazing mixture of wooly fur and prickles. His long slender snout looks like the bill of a bird. The mouth is a narrow opening in the tip. This strange animal lives solely on ants and termites This makes him an anteater, though he is not related to the aardvark anteater of Africa or the giant bear anteater of South America.

The platypus is about two feet long and the two cousins do not look much alike. The platypus has a snout like the bill of a duck, a thick coat of the softest fur and a wide furry tail. Unlike the echidna, who hates the water, he is built for swimming, diving and paddling in the mud, He feeds on worms, crustaceans and other morsels he finds in the mud by digging around with his famous duckbill.

Both the echidna and the platypus are burrowers. The echidna burrows in dry ground and the platypus prefers to live in a damp burrow by some muddy stream. Both are very shy animals, rarely if ever seen abroad by day,

Though both of these strange mammals lay eggs, they have different ideas about family life. The mother echidna, as a rule, lays but one egg a year. It is a round egg with a large yolk and soft shell, rather like the egg of a snake.

The egg is hatched in a pouch on the motherts tummy and there the baby echidna feeds on mother's milk. As the baby growsf its prickly spines develop. In time, Mama finds this uncomfortable and the little fellow is turned out of the pouch to make his own way in the world Mrs. Platypus rears her children in a deep burrow. Their nursery is a large chamber tenderly lined with gum leaves and other qomfortable bits of vegetation. As a rule, she lays two eggs, sometimes three. They too are like snake eggs, Mrs. Platypus has no pouch and just in case those precious eggs should get lost in their big nest: she sticks them together. Next she seals up the entrance to the nursery tunnel and gets down to the business of hatching the eggs. She holds them to her breast and wraps, her body around them in a furry ball. The babies hatch in about ten days and are fed on mother's milk. They develop very slowly and it is sever months before they are ready to come out of the burrow and take a look at the world,