

8UBMYT1LACKA. 



SUCCULATjE. 



appear* to be the fct in the eastward prolongation of the great levels 

 of Hat field Cliue along the actuary of the Hutnber, and much below 

 it* loveL De Luc suppose* Uie aame thing in regard to the peaty 

 deposit of Rotterdam, which rests on ailt, a* that repotee on sand. 

 lie regard* the whole u drirted by the river current*, and- as accu- 

 mulated below the river w.Ocrs. 



There are many examples of the occurrence in one deposit of sand, 

 clay, peat, timber, lacustrine shells, and bonea of quadrupeds. It is 

 rather characteristic of such combination* that there is only one layer 

 of peat with trees, that it lie* upon the clay, ami that in this clay are 

 the lacustrine ahell* and the bone* of quadrupeds. This general rule 

 applies to numerous small deposits on the coasts of Yorkshire and 

 Lincolnshire, including bones of deer, and to the larger area of the 

 Irish peat, which yields the bones of the gigantic elk ; and is exem- 

 plified in the American deposits which contain the mastodon. Beneath 

 the whole of theae deposits frequently lie the gravelly clays and sands, 

 with boulder* of diatant rook*, commonly called Diluvium. The 

 sheila ore usually of existing species, the trees of existing kinds, but 

 the quadrupeds (Beaver and Irish Elk for instance) often of races 

 locally or uuiver-ally extinct. 



It ha* been thought necessary in some cases to appeal to a local 

 change of the relative Uvel of land and sea for au explanation of the 

 ubmerged forests of the English and European coasts : sometimes 

 this may be avoided by assuming in ancient times a different condition 

 of the tides ; and sometimes it is unnecessary, because the trees may 

 be supposed to have been transported. It should seldom be granted, 

 because, in the very same district, the diluvium with its marine 

 hell* may be thought to be a ' raised beach,' and the submarine 

 forests to mark a real subsidence of the land. This is the case iii 

 Holderneaa, 



The antiquity of these buried forests is often beyond the reach of 

 inference, but in many inland districts the condition of the trees is 

 auch as to have led observer* to believe they were cut down or burned 

 down. In Hatfield Chace ('Phil. Trans.,' 1701) many of the trees 

 were thus destroyed ; some were evidently worked by the woodman's 

 tools of stone or wood, liomau coins were gathered from among the 

 roots ; and in one situation the ground b.-low seemed to have been 

 ploughed in ridge anil furrow. 



Examples of accumulations such as have here been generalised, are 

 abundant round all the shores of Britain, and are common in the 

 interior of the island. 



(De la Beche, Geological Manual; Lyell, Principle* of Geology; 

 Phillips, Trealiie on Geology, vol. ii. ; De Luc, JJisloire de la Terre ; 

 DC la Pryme, in the Phtlotopkical Traniactiont, abridged by Button ; 

 Traiuactunu of the Cornitk Geological Society, <tc., may be consulted 

 for details of phenomena and reasoning on the causes and date* of 

 their ooeurence.) 



SUBM YTILA'CKA, M. De Blainville's name for his sixth family of 

 Lamellibranckiata. 



The following is a definition of the Submytilacea : Mantle nearly 

 a* in the Mytilacea, that is to say, adherent, and slit throughout its 

 lower |rt, with a distinct orifice for the anus and a commencement 

 of a tube for respiration by mean* of a particular disposition of its 

 posterior extremity, which is furnished with tentacular papilla); a 

 Urge fleshy abdominal mass for locomotion, without byssua at its 

 hue; two distinct muscular impression*. 



Shell free, subnacreouc, regular, equivalve ; dorsal hinga lamellar, 

 ligament external ; two muscular impressions with the pallia! impres- 

 sion which unites them not excavated backward*. 



M. Do Blainville remarks that this family are more or less inhabitant! 

 of mud, and are locomotive by means of their foot. 



He divides them into two section* : 



1. The Limnoconchs (Limnodrrma, Poli). 



All these have an epidermis, are nacreous, and are inhabitants of 

 fresh water*. 



2. Specie* without any evident epidermis, not nacreous, 

 and more or leu pectinated. 



These are marine. 



Under this section U. De Blainville arranged but one genus, Cardita. 

 Animal resembling that of the Fresh- Water Muscles. [NAIAD.K.] 



Shell very thick, tolid, equivalve, often rery inequilateral; umbonet 

 recurved forward* ; binge with two unequal oblique te<th, one short 

 and cardinal, the other long, lamellar, bent, and placed much more 

 backward*; ligament elongated, *ubext*rnal, and sunk into the shell; 

 muscular impression* rather large and very distinct; pallia! impression 

 narrow. 



M. De Blainville divide* the genu* into the following section* : 



A. Elongated specie*, a little notched or gaping at the inferior 

 bonier; umbo nearly cephalic; ligament hidden. (The UyMi- 



. ! i i 



Example*, Cardita crauifoita, Adau*., 'Seneg.,' pi. 

 Caidita calyctUala, ' MalacoL,' pi. ay, fig. 1. 



15, f. 8; 



C. Specie* nearly round or luborbicular, with the inferior border 

 rounded, denticulated, and more and more equilateral; the two 

 teeth shorter and more oblique. (Qenu* Veuericardia, Lam.) 



Ex. Venericardia imbricata, ' MalacoL,' pi. 68, f. 3. 



D. Elongated and very inequilateral species; the umbo nearly 

 cephalic and recurved forwards ; two short cardinal diverging teeth 

 besides the lamellar tooth ; ligament very long, little or not at all 

 projecting ; abdominal impression sometimes a little directed back- 

 wards. (Qenus Cypricardia, Lam.) 



Cardita calyculata has the shell oblong, white, painted with lunate 

 brown spots; the ribs imbricato-squamoua ; the scale* arched and 

 iucuuibent. 



B. Oral specie*, with the inferior border nearly straight or a little 

 convex, crenuUted and completely closed. (The Cardiocardilv.) 

 Ex. Cardila Ajar, Allan- , Scneg.,' pi. 16, f. 2. 



Cardita calyculuta. 

 a, with the umboncs turned towards the spectator, showing the lunulc. 



Species of Cypricardia, Vencricardia, and Cardita occur fossil from 

 the Lower Silurian upwards. [VEXERID.E.] 



JVnwfeorrfi'.i (Cardila) imbritala. 

 Fosiil from Grignon. A variety found at Courtignon. 



SUBOSTRA'CEA, M. De Blainville's name for his second family of 

 LamcUiltranchiata. [1'nc.TiNlD.K ; SroxDVi.in.v:.] 

 SUBULA. [ESTOMOSTOMATA.] 



SUBULA'RI A (from ' subula,' an awl, from the form of the leaves), 

 a genus of Plant* belonging to the natural order Cmciferrr, and the 

 tribe !<ubulariece. It has an oval-oblong laterally compressed pouch, 

 with boat-shaped valves. 



S. aquatica, Awl-Wort, is a little aquatic stemless herb, with 

 fasciculnr simple white fibrous roots. The radical leaves are linear 

 and awl-shaped, the scapes naked and few-flowered, the pedicels 

 filiform and brsotless. It is a native of the colder parts of Europe, in 

 ditches, lakes, and rivulets with a sandy or gravelly bottom. It is 

 also found plentifully in the north of England, Scotland, and Ireland. 

 Sir W. Hooker and Sir J. E. Smith agree in stating that the flowers 

 always remain several feet under water, even during the time they are 

 expanded, so that, contrary to the general rule, fertilisation must 

 take place in that element. 



(Babiugtou, Manual of Britith botany, -Burnett, Outltnaof Jlolany.) 



SUBULICORNES. [NBUROPTBRA.] 



SUCCl'NEA, a genus of Pulmoniferous Gnsteropodous Molliuca, 

 belonging to the Volimacea of Lamarck and the Limacinca of De 

 Blainville. It is the sub genus Cochlohydra of Forussac. 



The ahell is ovate, rather elongated, with a large entire longitudinal 

 aperture, and a short spire ; the outer lip is thin, and continuous with 

 the delicate sharp-edged columella; the inner lip is spread over a 

 part of the body-whorl. 



Cuvier, who places the genus between Chondru* and Clatuilia, 

 remarks that the animal cannot withdraw itself into the shell entirely, 

 and that it may be regarded almost as a Tatacclla, with a large shell. 

 It has, he remarks, the lower tentacula vei-y small, and lives on the 

 herbage and plants on the brinks of streams, whence it has been 

 considered as amphibious. [HKUdD.E.J 



The most familiar specie* is tiuccincajiutrii.Iftlirpittrii of Linnaeus, 

 which is common in moist places, on the banks of fresh waters. 



SUCCINITE. [OABICET.] 



SUCCORY. [CicHOKiUJi.] 



SKCCULATVE, the name of a natural order of Plants in the 

 ' Fragments of a Natural System ' of Linmeus, adopted by Bartling 



