The average height of the crossed plants is here 20 inches, and that of the self-fertilised 17.12; or as 100 to 86. But this excess of height by no means gives a fair idea of the vast superiority in vigour of the crossed over the self-fertilised plants. The crossed flowered first and produced thirty flower-stems, whilst the self-fertilised produced only fifteen, or half the number. The pots were then bedded out, and the roots probably came out of the holes at the bottom and thus aided their growth. Early in the following summer the superiority of the crossed plants, owing to their increase by stolons, over the self-fertilised plants was truly wonderful. In Pot 1, and it should be remembered that very large pots had been used, the oval clump of crossed plants was 10 by 4 1/2 inches across, with the tallest stem, as yet young, 5 1/2 inches in height; whilst the clump of self-fertilised plants, on the opposite side of the same pot, was only 3 1/2 by 2 1/2 inches across, with the tallest young stem 4 inches in height. In Pot 2, the clump of crossed plants was 18 by 9 inches across, with the tallest young stem 8 1/2 inches in height; whilst the clump of self-fertilised plants on the opposite side of the same pot was 12 by 4 1/2 inches across, with the tallest young stem 6 inches in height. The crossed plants during this season, as during the last, flowered first. Both the crossed and self-fertilised plants being left freely exposed to the visits of bees, manifestly produced much more seed than their grand-parents,--the plants of the original clump still growing close by in the same garden, and equally left to the action of the bees. 5. ACANTHACEAE.--Thunbergia alata.