172 Objects for the Microscope. 



being perfect in itself, and distinguished from the Anthozoa 

 by that of its ciliated tentacles, which do not seize the prey, 

 but create currents in the water whereby food is carried 

 into the mouth. 



This is a great distinction, and must be observed, of 

 course, in the living animal ; a very curious sight it is to 

 watch the shoals of little golden fish-like naviculse whirled 

 into the vortex of a hungry polype, the currents running 

 along the cilia or delicate fringe which edges each tentacle. 

 Some polypes have two stomachs, one a kind of gizzard, 

 triturating the food, and the other digesting and discharging 

 the refuse. There is even a rudimentary liver a valve at 

 the pyloric opening ; the stomach itself is lined with cilia ; 

 in short, the living polype you are now looking at in 

 its dead state was a wonderfully organized little creature, 

 though scarcely visible to the naked eye. Instead of the 

 ovarian vesicles of the Anthozoa we find, especially on 

 Flustra and Lepralia, little pearly cells, which are gemmae, 

 or buds, thrown forth from the body of the polype. They 

 have two methods of propagation, one by gemmation, the 

 other by a true sexual generation. (See ' Carpenter on the 

 Microscope,' p. 575.) 



MEMBRANIPORA PILOSA. 



An abundant and beautiful zoophyte for examination in 

 the living state, as the fearless little polypes rise up in 

 crowds from the shelter of their pearly homes, and fling forth 

 their white ciliated tentacles,, waving, curling, contracting, 

 and expanding, in very ecstasy of life, drawing in the food 

 they require by means of the currents these tentacles make. 



In this living state the Membranipora is only a brown, 

 thick crust on rock or sea-weed ; but when the zoophyte is 

 dead, we find it on the brown fucus or the crimson Deles- 

 seria, or sheathing the stem of Chondrus crispus, like a 

 delicate net, pure white, or pale fawn colour; when mounted 

 dry it is perfectly lovely. We now see the oval horizontal 

 membranous cells, sharply toothed and granulated, whilst 

 behind the mouth of each is a long jointed bristle, which 

 in life lashed the water to and fro, keeping the Polypidoin 



