GRANTIA. 



[ 297 ] 



GRxVPIIIS. 



GRANTIA,Fleming. — Agenus of Sponges. 



Char. Form variable; firmish and inelastic, 

 usually white, with a close but porous tex- 

 ture, and composed of a gelatinous base, with 

 imbedded calcareous spicula; orifices distinct. 

 Marine. 



Spicula simple, radiate or stellate, com- 

 posed of carbonate of lime ; hence easily 

 distinguished from the siliceous spicula of 

 other sponges by their dissolving with effer- 

 vescence in a dilute acid. The organic basis 

 is stated not to be fibrous as in most other 

 sponges. 



The seven British species are found grow- 

 ing upon or from rocks, sea-weeds, shell-fish 

 and zoophytes, between tide-marks. They 

 vary in size from about the 1-10 to 3 or 4". 

 Gemmules have not been found in them. 



BiBL. Johnston, Brit. Sponges, ^'C. 

 p. \72; Grant, Outlines of Compar. Anat. 

 and Edin. New Phil. Journ. i. and ii. 



GRANULE-CELLS. — This term has 

 been applied to cells found in animal solids 

 and liquids, containing a number of globules 

 of fat or oil (PL 30. figs. /, 16a, 1/ e). They 

 are of variable size, perhaps the average may 

 be placed at 1-2000"; and are easily recog- 

 nized by the dark margins and light centres 

 of the globules, which are insoluble in acetic 

 acid and solution of potash. The cells some- 

 times contain a nucleus, at others not. The 

 term granvde-cells should properly be limited 

 to cells of new formation, as those found in 

 inflammation, cancer, &c. ; but it has been 

 so generally applied to cells of whatever 

 kind, containing fatty globules, that it has 

 no pathological signification. 



See Degeneration, Fatty, and In- 

 flammation. 



GRAPE-FUNGUS.— See Oidium. 



GRAPHIDEiE.— A family of Gymnocar- 

 pous or open-fruited Lichens, characterized 

 by irregularly-formed, mostly elongated 

 apothecia, with the margins closed in, or the 

 disk covered with a veil in the earliest state. 

 The excipulum either special or formed by 

 the thallus. 



Synopsis of British Genera. 



I. Opegrapha, Ach. Thallus crusta- 

 ceous or membranous. Apothecia {lirellce) 

 elongated, simple, or branched, sessile ; ex- 

 cipulum carbonaceous, entire or surrounding 

 the sides and base. The disk chink-like or 

 channelled with a proper border. 



IL Graphis, Ach. Thallus crustaceous 

 or membranous. Apothecia lirellaeform, im- 

 mersed ; excipulum carbonaceous, halved or 



confined to the side, the base being naked; 

 disk channelled, surrounded by a proper 

 border and an accessory one from the thallus. 



III. Hymenodecton, Leighton. Thal- 

 lus crustaceous or membranous. Apothecia 

 lirellseform, immersed; excipulum a very thin, 

 black, cartilaginous membrane, entire or sur- 

 rounding the sides and base ; disk broad, 

 plane, smooth, surrounded with a very 

 slender proper border and an accessory one 

 derived from the thallus. 



IV. CHioGRAPHA,Leight. Thallus mem- 

 branaceous. Apothecia lirellseform or sub- 

 discoid, sessile ; excipulum carbonaceous, 

 entire or surrounding the sides and base ; 

 disk plane, broad, surrounded by a proper 

 border and an accessory derived from the 

 thallus. 



V. AuLocoGRAPHA, Lcigliton. Thallus 

 membranaceous. Apothecia lirellaeform, 

 subimmersed, prominent ; excipulum carbo- 

 naceous, halved or confined to the sides, 

 palmatifid, the base naked ; disk chink-like, 

 closed, surrounded with a proper longitudi- 

 nally-furrowed border, and an accessory one 

 derived from the thallus. 



VI. Lecanactis, Eschweiler. Thallus 

 crustaceous. Apothecia lirellaeform or sub- 

 discoid, immersed ; excipulum carbonaceous, 

 entire or surrounding the sides and base ; 

 disk plane, open, pruinose, surrounded with 

 a proper border. 



VII. Platygramma, Leight. Thallus 

 crustaceous. Apothecia lirellajform, almost 

 simple or radiate; excipulum none; spori- 

 ferous layer free; disk plane, open, naked, 

 without any margin. 



VIII. Arthonia, Ach. T/ia//w5 cartila- 

 gineo-membranous. Apothecia roundish or 

 difformed, tumid, innately sessile, covered 

 with a subcartilaginous membrane, subgela- 

 tinous within, containing immediately under 

 the surface a series of pear-shaped thecae ; 

 no excipulum ; disk nearly plane, without a 

 border, black and rough. 



IX. CoNiocARPON, D.C. Thallus crus- 

 taceous. Apothecia appressed, roundish- 

 deformed or elongated, covered with a sub- 

 cartilaginous membrane, which ultimately 

 breaks up into a fine powder, subgelatinous 

 within, containing a series of pear-shaped 

 thecae ; no perithecium ; disk flat, depressed, 

 without a border, pruinose. 



BiBL. Leighton, Monogr. of Brit. Gra- 

 phidece, Ann. Nat. Hist. 2nd ser. vol, xiii. 

 1854. 



GRAPHIS, Ach. — A genus of Graphideae 

 (Gymnocarpous Lichens), containing several 



