ESCHARID^J. 399 



and which are also very distinct in the Notamia; but 

 which, in the present instance, would seem to have for 

 their chief function the drawing-up or corrugation of the 

 membraneous portion of the polype-cell. These muscular 

 fibres have a distinct central nucleus or thicker portion, 

 as is the case in the analogous muscles in some other 

 polypes. 



EscHARiD.dE. This interesting family justly deserves the 

 great attention many naturalists have bestowed upon it. 

 Linnaeus named it Flustra, from the 

 Saxon word flustran, to weave; it is 

 commonly called a Seamat, and re- 

 semble fine network spread over stones, 

 rocks, shells, and marine plants. This 

 network, when submitted to the powers 

 of the microscope, is found to be a 

 cluster of cells, in each of which dwells 

 an animal, that protrudes its feelers 

 when searching for food, and sinks into 

 its little home when tired, or alarmed by 

 approaching danger. 



Dr. Grant estimates that a single 

 Flustran has as many as four hundred 

 millions of cilia on these restless Fi g- 203. 



t i mi /. -I n . cornis, ea-moss po- 



feelers. The feelers vary from ten to iy pe; the animal is re- 

 twelve ; their organisation consists p Jj^ik ie ceii Ht f *** 

 of a long gullet, a gizzard, a stomach 

 and intestines; the body being a transparent substance. 

 Some take the form of a delicate minute tree, having cells 

 in all parts, and of various colours ; they inhabit every sea. 

 Lamouroux says : " When the animal has acquired its 

 full growth, it flings from the opening of its cell a small 

 globular body, which fixes near the aperture, increases in 

 size, and soon assumes the form of a new cell ; it is yet 

 closed, but through the transparent membrane that covers 

 its surface the motions of the polype may be detected ; the 

 habitation at length bursts, and the tentacles protrude; 

 eddies are produced in the water, and conduct to the 

 polype the atoms necessary for its subsistence. The aper- 

 ture of the cells is formed by a semicircular lid, convex 

 externally and concave internally, which folds down when 



