"It was a great surprise to me, sir," said Fred, "to learn that the stems as well as the leaves of plants differ, according to the kind of seed from which they spring. Our last year"s lessons taught us to look for net-veined leaves on a plant which grows from a seed with double seed-leaves, andfor parallel-veined leaves on one which comes from a seed with a single seed-leaf. We learn from our lesson to- day that the seed with the double seed-leaf produces one kind of stem, and the seed with a single seed-leaf a totally different stem.""Do you remember the other name for the seed-leaves, Fred?" asked Mr. Wilson.
"Yes, sir, they are called cotyledons. Those seeds which have only one seed-leaf are called mono-cotyledons; those with two seed-leaves are di-cotyledons.""Try and tell me all you can about the stem of the di-cotyledon." said Mr. Wilson.