REPTILIAN WATER TRESPASSERS. 



modified leaf, the outer membranes representing the 

 upper and lower epidermis of the leaf, and the soft, 

 juicy interior being a modification of the "parenchyma," 

 which in some leaves is very thin, but in others is very 

 thick and juicy. The leaves in question are of the kind 

 which are technically called " carpels/' and are those 

 of which seed-vessels are made. 



He saw in that one intuitive flash of genius that 

 the orange is, in fact, a whorl of leaves, and thus was 

 given the key to a great mystery hitherto concealed 

 from man, By means of this discovery one or two 

 apparent anomalies are easily explained. There is 

 a variety of orange, known by the name of the Female 

 Bigarade. It is a large, coarse, deep yellow fruit, which 

 has the peculiarity of being double, one orange being 

 enclosed within another. Although this fact had been 

 known for many years, no botanists could account for 

 it, and it was left for the poet Goethe to supply the 

 key to the mystery. When this is understood, the 

 structure of the double orange is easily understood. It 

 consists of two whorls of carpels on the same stem, the 

 upper and smaller whorl being consolidated into the 

 central fruit, and the lower and larger whorl encircling 

 it. In some cases, three oranges are found one within 

 the other. 



Other curious varieties of the orange tribe are also 

 accounted for in the same manner. For example, there 

 is the Fingered Bigarade, in which the fruit is divided 

 into finger-like globes ; the Horned Bigarade, in which 

 the fruit is deeply ribbed, and has its sides projecting 

 into horns ; and the enormous Chinese Fingered Citron, 

 in which the fruit is entirely divided into long, finger- 



