RELIQUIA. 



llie fpecific charafter or diagnofis, and the general de- 

 fcriptfon. 



The fpecific charaflcr contains the marks that diltiiiguifh 

 the fpecies to which they belong, from all others in the fame 

 genus. Specific charafters of roliquia fliould be fo con- 

 Sruftcd as to diftinguifh permanent from temporary fpecies ; 

 and thofe whoi'e originals have not, as yet, been difcovtred. 

 The fpecific charafter of the recent fpecies of plants or ani- 

 mals frequently depends on parts often or conilantly wanting 

 in the foflile fubjeft. When that is the cafe, another diag- 

 nofis muft be given to diftinguifh the reliquium ; that of the 

 recent fpecies being marked as a parenthefis. The generic 

 and trivial names are prefixed to the fpeciiic character. And, 

 generally, the name of the family, or fubdivifion of the 

 genus to whicli tlie reliquium belongs : after which is to be 

 detailed in diftiiift clades, I. The fynonyms or names by 

 -which the fpecies has been diltinguithed by authors, with 

 references to the figures given of it. 2. The varieties of 

 'the fpecies, with their fynonyms. 3. The vernacular name. 



4. The mode or ftate in which the reliquium is found. 



5. Its foil or geological fituation. 6. Its geographic fitu- 

 ation, and then the general defcription. 



The defcription delineates in appropriate terms all the parts 

 conilituting the effcnlial form of the reliquium, according 

 to their number, figure, proportion, and fituation : it mull 

 primarily refer to the original of the reliquium, as no jull or 

 p'erfeft delineation of the fpecies can be given, until the nature 

 of its prototype be afcertained. 



The terms employed in defcribing reliquia, which derive 

 their form from the external parts of animals and plants, muft 

 be thofe ufed by zoologifts and botanifts of the Linnxan 

 fchool. But thofe which derive their form from the internal 

 parts of organic bodies, are to be defcribed in fuch terms as 

 anatomifts would ufe in diftinguifliing the fame parts in the 

 recent fubjefts. 



As appendant parts to the general defcription of the reli- 

 quium muft be given, I. An enumeration of the fpecimens 

 which exhibit the various accidental forms under which the 

 fpecies has been found. 2. An enumeration of the various 

 fubftances which have been obferved asconftituting the reli- 

 quium and its matrix. 



Having given this brief account of Mr. Martin's fcientific 

 delineations of reliquia, we fhall prefent our readers with 

 the fubftance of two very interefting communications fent 

 to the Royal Society fince the printing of the article Petri- 

 factions. Of thefe, the firft is " An Account of fome Orga- 

 nic Remains found by Mr. Trimmer, near Brentford, in 

 Middlefex." 



*' The fpecimens," fays Mr. Trimmer, " have been col- 

 leftedfrom two fields, not contiguous to each other ; there- 

 fore, to avoid confufion, I (hall take each field feparately, 

 firft defcribing the Itrata as far as they have come within my 

 knowledge, and afterwards I ihall fpeak of the organic 

 remains as they were refpeftively found in thofe ftrata. 



" The firft field is about half a mile north of the Thames 

 at Kew bridge ; its furface is about twenty-five feet above 

 the Thames at low water. The ftrata here are, firft, fandy 

 loam from fix to ft ven feet, the loweft two feet flightly 

 calcareous. Second, fandy gravel, a few inches only in 

 thicknefs. Third, loam fiightly calcareous, from one to five 

 feet : between this and the next ftratum, peat frequently 

 intervenes in fmall patches, of only a few yards wide, 

 and a few inches thick. Fourth, gravel containing water ; 

 this ftratnm varies from two to ten feet in thicknefs, and 

 is always the deepeft in the places covered by peat ; in 

 thcfe places the lower part of the ftratum becomes an hete- 

 rogeneous mafs of clay, fand, and gravel, and frequently 



exhales a difagrceable muddy fmell. Fifth, the main (Iratam 

 of blue clay, which lies under this, extends under London 

 and its vicinity ; the average depth of this clay has been 

 afcertained, by wells that have been dug through it, to be 

 about two hundred feet under the furface of the more level 

 lands, and proportionally deeper under the hills, as appear* 

 from lord Spencer's well at Wimbledon, which is five hundred 

 and fixty-fcven feet deep. This ftratum, befides figuicd fof- 

 fils, contains pyrites and many detached nodules ; at the 

 depth of twenty feet there is a regular ftratum of thefe 

 nodules, fome of whicli are of very confiderable fize. 



"In the firft ftratum, as far as my observation has extended, 

 no remains of an organized body has ever been found, and 

 as my fearch has not been very limited, I may venture to 

 fay it contains none. In the iecond itratum, fnail-fhells, 

 and the (hells of river fifli, have been found, and a few bones 

 of land animals, but of inconfiderable fize, and in fuch a 

 mutilated ftate, that it cannot be afcertained to what clafs 

 they belong. In the third ftratum, the liorns and boneS of 

 the ox, and the horns, bones, and teeth of the deer, iiave 

 been found, and alfo, as in the fecond ftratum, fnail-ftiella, 

 and the fhells of rivcr-fifli. In the fourth ftratum were 

 found teeth and bones of both the African and Afiatic 

 elephants, teeth of the hippopotamus, bones, horns, and teeth 

 of the ox. 



" A tufi< of an elephant meafured, as it lay on the ground, 

 nine feet three inches, but, in attempting to remove it, it 

 broke into fmall pieces. When this ftratiim dips into the 

 clay, and becomes a mixed mafs, as before ftatcd, it is fel- 

 dom without the umains of animals. In the fifth ftratum, 

 namely, the blue clay, the extraneous foflils are entirely 

 marine, with the exception of fome fpecimens of fruit and 

 pieces of petrified wood, the latter of which may be confi- 

 dered as marine, becaufc, when of fufficient fize, they 

 are always penetrated by teredines. Tlie other foffils 

 from this ftratum are nantilij oyfters, pinnae marins, crabs, 

 teeth and bones of fifii, and a great variety of fmall marine 

 fiiells ; this ftratum has been penetrated hitherto in this field 

 only to the depth of thirty feet, throughout which the fpe- 

 cimens found were difperfed without any regularity. 



'• The fecond field is about one m.ile to the welUvard of the 

 former, one mile north of the Thames, and a quarter of a 

 mile to the eallwardof the river Brent ; its height above tlie 

 Thames, at low water, is about forty feet. The ftrata are, 

 firft, fandy loam, eight or nine feet, in the loweft three feet 

 of which it is flightly calcareous. Second, fand, becoming 

 cparfer towards the loweft part, and ending in landy gravel 

 from three to eight feet. Third, fandy loam highly calca- 

 reous, having its upper furface nearly level, but gradually 

 increafing in thicknefs from a feather-edge to nine feet. 

 Below this are two ftrata of gravel and clay, as in the other 

 field ; but as thefe ftrata have been only occafiop.ally pene- 

 trated in digging for water, nothing therefore is known with 

 refpeft to them, but that they exift there. 



" In the firft ftratum, as in the other field, no organic re- 

 mains have been obferved. In the fecond, but always within 

 two feet of the third ftratum, have been found the teeth and 

 bones of the hippopotamus, the teeth and bones of the ele- 

 phant, the horns, bones and teeth of fevera! fpecies of deer, 

 the horns, bones and teeth of the ox, and the fliells of river- 

 fifti. 



" The remains of hippopotami are fo extremely abundant, 

 that, in turning over an area of 1 20 yards in the prefer.t 

 feafon, parts ot fix tu(ks have been found of this animal, 

 befides a tooth and part of the horn of a deer, part of a tuik, 

 and part of a grinder of an elephant, and the horns, with a 

 fmall part &f the ikuU, of an os. One of thefe horns I had 



an 



