204 THE MICROSCOPE. 



species is somewhat peculiar, each of the primary and secondary 

 branches springing out at an angle of 40 or 50. That part of 

 the stem which bears the denticles is waved so as to bear each 

 denticle on the projecting part; the denticles are elliptic, and the 

 mouth of each apparently a little hollowed inwards, perhaps arising 

 from the extremity being fractured; the vesicles are ovate, with four 

 or five blunt teeth surrounding the mouth, and divided into six or eight 

 portions by annulated undulating lines. It might be classed among 

 the large and strong SertularidaB, the principal shoot being of the thick- 

 ness of a sparrow's quill at its base, and four inches or five inches long. 

 The branches shoot forth from opposite sides; the whole coralline thus 

 assuming a flat form, to the extent of four or five inches. 



On the south-eastern coast of England the most common kind found 

 is the Sertularia setacea, which, after rough weather, is cast on the 

 shore attached to sea-weed. The stem and branches seem composed of 

 separate pieces, fitting into each other as some foreign trees do, and 

 terminate in a star-like head, from which radiate the feelers or arms. 

 Dr. Mantell states he was present on one occasion when Mr. Lister 

 was observing ,a living specimen : a little globular animalcule swam 

 rapidly by one of the expanded polyps, the latter immediately con- 

 tracted, seized the globule, and brought it to the mouth or central 

 opening by its tentacula; these gradually opened again, with the ex- 

 ception of one, which remained folded, with its extremity on the ani- 

 malcule. The mouth instantly seemed filled with cilia, which, closing 

 over the prey, was carried slowly down its stomach; here it was im- 

 perfectly seen, and soon disappeared. 



Appertaining to this family are the Thuiarea, so named from re- 

 sembling a cedar-tree ; but some kinds look more like a knobbed thorn- 

 stick with a bottle-clearer at the top; others resemble a fir-tree. 

 Antennularia are so called from resembling the lobster's antenna. 

 They are found fixed to shells and rocks, are plentiful on the north- 

 eastern coast of England and the coast of Ireland. They are of a brown 

 colour, and covered with hair-like little branches ; and as the hairy 

 process is continued up its jointed stem, it is sometimes denominated 

 Sea-beard. 



The Plumularia, so named from the shoots and offsets being 

 plumous, are an extensive and beautiful branch .of this family. Pro- 

 fessor Grant thus describes the Plumidaria falcata : " This species is 

 very common in the deeper parts of the Frith of Forth ; its vesicles are 

 very numerous, and its ova are in full maturity at the beginning of 

 May. 'The ova are large, of a light-brown colour, semi-opaque, nearly 



