HI 



GECARCINUS. 



1, a (troop of the tubes of Ga*lroefi<rna modiolinn, T.am. (Mediterranean) ; 

 one of the tube* is broken and shows the valves in situ ; 2, FHIUI Sotx 

 (Grignon) eat open to show the clavatc tube of a small fossil (liulrodnrna ; 

 3, a worn fragment of a Madrepore, broken to show the tube formed by a 

 specimen of Gatlrochitna emtiforma, Lam. ; 4 and 5, two views of the two 

 ralTes of the last. mentioned specie*. ( From the ' Genera of Recent and Fossil 

 Shells,' bj O. B. Sowerbjr.) 



unite* with them. These tubes are very regular and curious in some 

 of the exotic species, especially in those which live buried in sand. 

 Thin habit is not merely the living habitually and freely in sand, as 

 the Razor-Fish do, but rather the treating of it in the manner of a 

 substance bored into ; and the tubes are to be regarded as the 

 linings of the perforations so made. All the species of the family 

 are borers, most of them preferring calcareous rock." 



For an account of faxicava see LrrnorHAOiDJE. 



OASTROCH^INID^E. [GASTROCH^NA.] 



GASTROMARGAa [QPADRCMASA.] 



OAULT. JCBALK FORMATION.] 



GAULTHERIA, a genus of Plants belonging to the natural order 

 Srieacat. It has a 5-cleft or 5-toothed calyx, bibracteato at the base, 

 after flowering becoming large and succulent, and covering the capsule 

 with a baccate coating. The corolla is ovate, ventricose, with a 5-cleft 

 revolute border, transparent at the base. There are 10 stamens, 

 inclosed, with flat filament* ; anthers bifid at the apex ; lobes biarigtatc. 

 The hypogynoua scales 10, usually united at the base. The ovarium 

 half inferior. The capsule 5-celled, with a looulicidal dehiscence. 



O. procumbent, Partridge-Berry, Chequer-Berry, Bosberry, Mountain- 

 Tea, is found on sterile sand and gravel in mountainous forests in tin; 

 driest situation in North America. It has a horizontal woody 

 rbizoma, often a quarter of an inch in thickness. The branches are 

 ascending, but a few inches high, round and somewhat downy. The 

 leaven are featured near the extremities of the branches, evergreen, 

 coriaceous, shining, ovml or obovate, acute at both end*, revolute at 

 the edge, and furnished with a few small scrratures, each terminating 

 in a bristle. The flowers are axillary, drooping, on round downy 

 rtalkit. There are two concave heart-shaped bracts. The calyx is 

 white, cleft into 5 roundish acute segment*. The corolla is whit.-, 

 urceolate, 5-angled, contracted at the mouth, the limb divided into 



5 short reflexed segments. The filaments white, hairy, bent in a 

 semicircular manner to accomodate themselves to the cavity between 

 the corolla and ovary. The anthers oblong, orange-coloured, ending 

 in two double horns, bursting outwardly for their whole length. 

 Above the filaments the pollen white. The ovary is roundish, 

 depressed, 6-angled, resting on a reddish 10-toothed glandular disc ; 

 the style erect, straight ; the stigma simple. The fruit is a small 



6 celled many-seeded capsule, invested with the calyx, which becomes 

 large, round, and fleshy, having the appearance of a bright scarlet 

 berry. The fruit contains an aromatic sweet highly pungent volatile 

 oil, which is antispasmodlc and diuretic. A tincture has been useful 

 in diarrheas. Cox states that the infusion it .useful in asthma. It 



is used in North America as tea, and brandy in which the fruit has 

 been steeped is taken in small quantities, in the same way as 

 common bitters. The oil is known under the name of Oil of 

 Wintergreen, and is used by druggists to flavour syrups, and also by 

 perfumers. 



'/'. ShaUon is a native of North America on the falls of the Columbia, 

 and near the Western Ocean. It has a procumbent hairy stem, 

 ovate subcordate serrated leaves, glabrous on both surfaces, the 

 racemes secund bracteate, clothed with rusty down. The corolla is 

 white tinged with red, downy, urceolate, with a closed limb. Tim 

 berries are globose, acute, fleshy, and purple. This plant grows in 

 the shade of close pine-forests wheru hardly anything else will grow, 

 which makes it a very desirable shrub for plantations. The berries 

 are much esteemed by the natives on account of their agreeable 

 flavour. 



6. hitpida, Wax-Cluster, is a native of Van Pit-men' Land ; 

 it has long lanceolate serrulated leaves, pilose beneath as well as on 

 the petioles; the branchleta hispid ; racemes axillary and termiiml, 

 shorter than the leaves ; the rachis and pedicels downy ; the calyxes 

 baccate, fruit and ovaries glabrous, the stem erect. It bears snow- 

 white berries, with a flavour by no means unpleasant ; in taste it is 

 said to resemble the gooseberry, but is somewhat bitter. According to 

 some Q. antipoda is said to have more merit as a fruit 



The species are all ornamental, and grow best in a peat soil. 



(Lindley, Flora Mtdica ; Lindley, Vegetable Kingdom; Don, 

 Dichlamydcoiu Plantt.) 



GAVIAL. [CHOCODILID.*.] 



. [BoviD*.] 



GAYAL. 



GAY-LUSSITE, a Mineral, occurring in oblong crystals in a lake in 

 Maricoibo, South America. It is a hydrous compound of the 

 carbonates of lime and soda, (Dana, Mineralogy.) 



GAZELLE. [ANTILOFEJ:.] 



GEBIA. [THALASSINIANS.] 



GECARCI'NUS (Leach), the name of a genus of Brachyurous 

 Decapod Crustacea, known familiarly to the English as Land-Crabs, 

 and to the French by the appellations of Tourlouroux, Crabes IVim . -. 

 or Crabes Violets, some of these terms being applicable not only t<> 

 different species, but to the same species at different ages, so that 

 those various names cannot be depended upon as specific designations. 



Latreille placed this tribe of crabs immediately after Pinnotheres. 

 He seems to admit Playtmu and Graptu* into the same section with 

 the Land-Crabs, properly so called ; and next to Grapnu come the 

 Orbiculata (his fourth section), containing Coryitet, tic. 



Desmarest places Gecarcintu at the head of the Quadrilateral of 

 Latreille, and arranges all the true Land-Crabs under that generic 

 title, which is preceded by Pitumnut, and succeeded by the Orbiculata, 

 of Latreille. 



M. Milne-Edwards makes the Gecarcinians the second tribe of his 

 family of Catametopes ; and in his arrangement they stand between 

 the Thelpusians, the first tribe, and the Pinnotherians, the second 

 tribe of that family. 



According to the last-named author the tribe of Gccarcinians is one 

 of the most remarkable groups of the class Crustacea; for it is 

 composed of animals breathing by means of bronchia:, or gills, and 

 yet essentially terrestrial, so much so indeed, that they would perish 

 from asphyxia if submerged for any length of time. They may be 

 distinguished easily from the rest of the family by their nearly oval 

 carapace, which is much elevated and convex above. The branchial 

 regions are in general very distinct, and project much below, occu- 

 pying nearly two-thirds of the surface. The front is very nearly as 

 large as the buccal frame (cadre lmcc.il), and strongly curved below. 

 The orbits are suboval, moderate, and very deep. The lateral borders 

 of the carapace are very much arched, and generally describe a 

 semicircle. The internal antennic are lodged under the front, and 

 fold back transversely in narrow and often nearly linear excavations. 

 The disposition of the external antenna} varies, and so do the jaw- 

 feet (pates-mltchnires) ; sometimes the fourth joint is inserted at the 

 external angle of the preceding, and remains exposed, as in tho 

 Ocypodians, and sometimes it is entirely hidden under its internal 

 surface. The feet of the first pair are long and strong; the suc- 

 ceeding feet are robust and long, and very nearly equal in size, and 

 their tarsus is pointed and quadrilateral. The abdomen of the male 

 is received in a deep excavation of the sternal plastron, and its second 

 articulation reaches nearly always to the base of the posterior 

 It is in general so long that it comes up to the base of the mouth, 

 and the appendages hidden beneath it are remarkably large. The 

 bninchitc are generally seven in number, namely, five fixed to the 

 vault of the sides, and two, in a rudimentary state, hi'Mcn under the 

 base of the preceding, and taking their origin from the jaw-feet ; 

 but in some species there are nine on each side. The respiratory 

 cavity is very large, and is raised into a vault highly elevated above 

 the bronchia;, so that above those organs there is a large empty space. 

 The tegumentary membrane with which it is lined is also very 

 spongy, and sometimes forms a fold along the lower edge of the 

 cavity, so as to form a kind of gutter, or longitudinal trough for 

 containing water when the animal remains exposed to the air. 

 (Milne-Edwards.) Observations on this curious reservoir were com- 

 municated to the Royal Academy of Science* in Franca by Messrs. 



