BOTANICAL SUBJECTS. 307 



What wonder is it then, considering that all our land plants 

 must have descended from seaweeds, that the Citrus and several 

 other land plants should have inherited on their fronds remnants 

 of those very conceptacles which in the modern Fucus are found 

 also abortive, except in the specialized parts ? The Citrus, long, 

 long ago, grew out of the habit of evolving germ and sperm cells 

 out of its leaves proper. It now evolves them out of modiHed 

 leaves — the stamens and carpels, — but it has not got entirely rid of 

 the remnants, on its leaves, of its former reproductive organs. 

 However we may refuse to see any close connection between an 

 orange-tree and a Fucus, nevertheless, from an evolutionary point 

 of view, we cannot deny them relationship. 



The cellules of the oil-glands might, without much stretch of the 

 imagination, be looked upon as spores, degenerated into the fatty 

 matter of the essential oil, in the same way perhaps that ova of 

 animals are said to degenerate into fatty matter when no longer 

 needed as ova. They then are turned to a different use, and serve 

 a totally different end in the struggle for life. 



We now feel more than convinced that the splint bones in the 

 horse's foot are remnants of two other digits [in a three-toed an- 

 cestor, yet it will probably be considered a preposterous attempt to 

 try and descend to the conceptacles of a Fucus-like plant for the 

 explanation of these remnants in the Citrus frond ! 



Some might say that it is too ridiculous to tell us that the 

 delightful orange has had a Fucus for a remote ancestor. But it 

 seems just as ridiculous, or as wonderful, that man (made in the 

 image of Grod) should have come from a one-celled ovule, and in 

 his development have passed through the images of a fish, a 

 lizard, a dog or other mammal, and have finally bloomed into a 

 philosopher. 



More curious and suggestive still is the surface of a 3£illipora, 

 a form of low animals not very distant from the calcareous sea- 

 weeds. They have their surface covered with pores, not only 

 large and small, like the oil-glands of the Citrus leaf, but disposed 

 exactly like them. Fig. 131 (A and^ B) shows the surface of 

 Millipora and Fig. 132 (C and D) that of the Citrus leaf. 



This is what Prof. Nicholson says of the Millipora alcicornis, 

 " Its calcareous skeleton is usually in the form of a foliaceous or 

 laminar expansion, or is simply branched.** In this calcareous 



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