34$ THE BIOLOGY OF THE SEASONS 



jetsam. They consist in large proportion of " animated 

 sea-water," and it is instructive to watch them in all stages 

 of evaporation till only a thin transparent disc is left on the 

 sand. One remembers the striking fact that quite a number 

 of extinct genera have been described from their exact 

 impress on fine-grained rocks. Jelly-fishes are obviously 

 open-sea animals, and their abundant occurrence on the 

 shore illustrates wastage. They have lost their bearings 

 or got into the grip of inshore currents. 



Sometimes tossed up together are two creatures which 

 are almost violently contrasted, though, as a matter of fact, 

 they are not very distantly related, namely, Dead Men's 

 Finger (A Icyonium) , a flabby, fleshy colony with no pretence 

 to elegance, and the Sea-Pen (Pennatula), a graceful plumose 

 colony with a central axis and the polyps arranged on 

 pinnules up each side, like the barbs of a feather. 



There is sometimes a whole bank of the flexible tubes 

 of Lanice conchilega, a worm that binds shell fragments 

 and sand-particles together, literally " making ropes of 

 sand," and there is never difficulty in finding calcareous 

 worm-tubes, like those of Spirorbis, attached to the seaweed, 

 or those of Serpula on shells and stones. Now and again 

 among the seaweed we find the sea-mouse, Aphrodite, like 

 an entangled fragment of a rainbow, so iridescent is it. 



Piled up in great quantities often are the fronds of the 

 sea-mat (Flustra), leaf -like or seaweed-like till the eye 

 catches the innumerable small holes tenanted by the 

 animals forming the colony. The biologist handles it 

 with some affection, for was it not the subject of Darwin's 

 first scientific paper? And those who enjoy "beauty- 

 feasts " cannot do better than give some time to the 

 numerous calcareous relatives of the sea-mat which form 

 exquisite growths on shells and stones. In illustration of 

 contrast between two types not very distantly related, 



