History of British animals - University of Guam Marine Laboratory

Halichondria. ZOOPHYTA. SPONGIADiE. 521Crust extended sometimes an inch in thickness ; when dried, the surfaceis flat and very porous, and the orifices, which are rather sunk, have irregularmargins, and the divisions of the interior canals being usually visible,give the openings a stellular aspect. When dry, it isremarkablyam friable. Iinclined to consider this species as the S- fava of Montagu, Wern. Mem.ii. 115. He says, "This sponge, though harsh to the feel, yields to thepressure of the finger nail without elasticity when recent ;is orange-yellow,and full of gelatinous flesh, but when exposed for a time on the shore, andthe fleshy parts decayed and washed out, the pores are observed to be roundish.When examined by a lens, has a slight resemblance to a honey-comb ;the pores, however, are not regular in size. If taken fresh and artificiallydried, the pores are greatly obscured by the contracted gluten, and the colourbecomes of a dark brown. If it has undergone a natural decomposition ofthe more perishable parts on the sea-shore, by the conjoined action of thewater and the air, the pores are cleared, and it retains a light yellowish colour.A specimen in this state before me, is flat, and broad ; round the edges(which appear to have been broken) there are many large round openings intersectingthe smaller pores, and communicating with those on the flat surfaces.This piece is three inches long, two broad, and about half an inchthick.95. H. parasitica.— Substance rather loose, harsh to the feel,and somewhat brittle ;spicula slightly curved, and pointed atone extremity.Mont. Wern. Mem. ii. 114.— Investing fuci and corallines, not uncommon.Surface rough, with the extremities of fasciculated spicula ; pores angular,unequal; orifices scattered, slightly elevated, with the margins notthickened.96. H. cinerea.— Three inches long and one broad, circular, alittle depressed ; pores minute, unequal ; orifices scattered, few,spicula short, curved, and double pointed.Spongia cin. Grant, Edin. New Phil. Journ. ii. t. ii. f. 3.— On rocks,Frith of Forth, rare.About half an inch thick, blackish-grey, the surface smooth, convex, fleshyand transparent.rounded inoscula-97. H. columba.— Irregularly latticed byting branches ; spicula double pointed and curved.Spongia col. Walker's Essays, 1 26.—S. cancellata, Sovier. Brit. Misc. i.131, t. vi Icolumbkil, Dr Walker; Brighton, Mr Fellows.Branches about a quarter of an inch thick ; pores minute, angular the;orifices, seated chiefly at the union of the branches, are conical, wide, withthe margins not thickened. As this species is different from either the S.cancellata of Gmelin or Lamarck, I have ventured to change the name, imposedby Mr Sowerby, for the term employed by Dr Walker, in the convictionthat the sponge referred to by both is identical.98. H. sanguined.— Colour deep blood-red, encrusting ; spiculalong, curved, single-pointed.Spongia sanguinea, Grant, Edin. New Phil. Journ. ii. t. ii. f. 9—Shoresof the Hebrides.Crust on the under surface of exposed rocks, sometimes six inches in dia^meter, and with a thickness of more than half an inch ; general surface flat,