1045 



TESTACELLUS. 



TETRAONID^E. 



1046 



in geological classifications, it is not the less true that the geological 

 date of the epoch of this period, the line of separation between it and 

 the tertiary eras, is entirely unknown by direct and positive facts, and 

 appears incapable of determination by reasoning on any collateral 

 phenomena at present ascertained. 



(Lyell, Principles of Geology; De la Beche, Geological Manual; 

 Phillips, PalcEozoic Fossils of Devon.) 



TESTACELLUS, the name of a genus of Pulmoniferous Mollusca. 

 T. Maugei may be given as an example. This form appears to have 

 been first noticed by M. Dugue", in a garden at Dieppe in 1740 : but it 

 does not seem to have attracted much attention tUl M. Mauzd, some 

 years since, brought home specimens from the island of Teneriffe. It 

 has also been found in several parts of France, and in Spain, and more 

 recently in a garden at Bristol. 



Shell of Tataeellus Mavgri. a, inside ; b, outside. 



Tntaeellui J/aitfrf. a, shell in iitu. (O. B. Sowerby.) 



TESTUDINARIA, a genus of Dictyogenous Plants belonging to 

 the natural order Diotcoreaceet. 



T. Elephantipa, the Elephant's-Foot Plant, is well known in our 

 collections of plants from its curious truncate rootstock, looking like 

 an elephant'* foot. It is covered with a soft corky bark, which is split 

 so as to give it a rough character. From the top of this thick mass a 

 climbing stem is sent, which bears the leaves and flowers. Like the 

 rest of Dietyogens this stem has not the regular division of the parts 

 of the stem seen in most Exogenous Plants. 



TESTUDINATA. [CHELONIA.] 



TESTU'DO. [CHELONIA.] 



TETE.' [SENKA.] 



TETHIUM. ISPONQIAD*.] 



TETHYS. [NUDIBRANCHIATA.] 



TETRABRANCHIATA. [BELEMNITE ; BELLEBOPHON ; CEPHALA- 

 PODA; QOHIATITES; NACTILID.S ; OCTOPODA; SEMAD.E; SPIIWLID^E; 

 TEUTHID.S.] 



TETRACAULODON. [MASTODON.] 



TETRACERUS. [AWTILOPEJE.] 



TETRACLITA. [CIBBIFEDIA.] 



TETRADYMITE. [BISMUTU.] 



TETRAD Y'NAMOUS (from Tfrrapcs, four, and Svvafus, power), a 

 botanical term employed by Linnaeus to indicate the character of those 

 flowers which, possessing six stamens, have two of them shorter than 

 the other four. [CRUCIFEB.E ; SYSTEM, SEXUAL.] 



TETRAGONA. [ACALEPH^] 



TETRAGONIA'CE^:, Aizoont, a natural order of Exogenous Plants. 

 It includes the genera Tetragonia, Aizoon, Sesuvium, and Miltus, which 

 are generally placed in the order Ficoidece, or Meiembryacece. The 

 reason given by Dr. Lindley for this separation is the want of petals 

 in these genera, as ho considers that the tendency to produce petals in 

 the Meiembryacece is of too powerful a nature to admit exception. 

 The relation of these apetalous Picoidece to Chenopodiacece is so strong, 

 that Dr. Lindley Bays " there is no character to distinguish them except 

 their ovary being formed of several carpels." 



Tetragonia expansa is a native of New Zealand and Japan, and is 

 used by the natives of those countries as a remedy in those forms of 

 cutaneous disease called scorbutic. The Aizoon Canarieme and A. Hit- 

 paniatm grow on the sea-coasts of the Canary Isles and Spain, and are 

 amongst the plants which yield soda after burning. 



TETRAQONO'LEPIS, a genus of Fossil Fishes. [Fisn.] 



TETRAGONO'LOBUS (from TiTTOffS, four, yuvla, angle, and \6ftos, 

 lobe), a genus of Plants belonging to the natural order Leguminosce. 

 It contains herbs with broad leafy stipules, trifoliate leaves, winged 

 petioles, xlternate leaflets, and flowers seated on axillary peduncles, 

 furnished with a bract. The calyx is tubular 5-cleft, the wings shorter 

 than the vexillum ; the stigma is funnel-shaped and beaked ; the legume 

 is cylindrical, furnished with four foliaceoua wings, which give it a 

 4-cornered appearance. 



T. purpuretu, Purple-Winged Pea, is a pilose plant with decumbent 

 stems, entire obovate leaflets, bracts longer than the calyx, and a 

 glabrous legume, with globose seeds. It is a native of the south of 

 Europe, and has dark purple flowers ; a variety is however found with 

 flowers of a dark-yellow colour. 



There is also a variety called T. p. minor, in which the stem, leaves, 

 and legumes, are much smaller. The unripe legumes are cooked and 

 eaten in the same manner as we eat French beans. 



There are four other species of Tetragonolobus, all of them inhabitants 

 of Europe. 



TETRA'NTHERA, a genus of Plants belonging to the natural order 

 Lauraceas. The flowers are dicecioua, some hermaphrodite, involucrated. 

 The calyx 6-parted, the segments nearly equal or wanting. The fertile 

 stamens generally about 9, in the petaloid flower from 12 to 21. The 

 leaves are variable, with pinnate veins. 



T. Roxburghii is a variable plant, a native of the mountains of India 

 and China. The fruit is globose, black, and about the size of a pea, 

 yielding a kind of greasy exudation from which the Chinese manu- 

 facture candles of a bad quality, and which serves as a basis for salves. 

 This fixed oil is supposed to constitute the principal part of the fruit 

 of Persea gratissima, so much esteemed in the West Indies under the 

 name of Avocado Pear. 



TE'TRAO. [TETRAONHXE.] 



TETRAODON. [TETKODON.] 



TETRAOGA'LLUS, a genus of Birds, placed by Mr. G. R. Gray in 

 the sub-family Lophophorina, of the family Phasianidce. 



TETRAO'NID^E, a family of Rasorial Birds, to which the Common 

 Grouse belongs. 



Linnaeus, in his last edition of the ' Systema Naturae,' places the 

 genus Tetrao at the end of his fifth order, Gallince, next to the genus 

 Nvanida. The Gallince come between the Grallce and the Passeres ; 

 the genus Strut/iio is the last of the order Grallce, and the genus 

 Columba the first of the order Passeres. 



The Liunsean genus Tetrao is very extensive, comprising not only the 

 true Grouse, but also the Franeolins, Partridges, and Quails. 



Cuvier, in his last edition of the ' Regne Animal,' arranges the 

 Te'tras (Tetrao, Linn.) under his fourth order, Galliuacds (Gallince, 

 Linn.), placing them between the Pheasants (Phasianus, Liuu.) and 

 the Pigeons (Columba, Linn.). 



This great genus in the arrangement of Cuvier is more compre- 

 hensive even than that of Linnaeus, for it includes the following sub- 

 genera : 1, Les Coqs de Btuyore (Tetrao, Lath.) ; 2, the Lagopedes, 

 or Snow Partridges (Perdrix de Neige) ; 3, the Ganga, or Attagen 

 (Pterocles, Temm.) ; 4, the Partridges (Perdix, Briss.), comprising the 

 Franeolins, the ordinary Partridges, the Quails, and the Colius, or 

 Partridges and Quails of America; 5, the Tridactyls (Lacep., Hemi- 

 podiui, Temm.), including Turnix, (IJonap., Ortygis, 111.), and Syrrhaptcs, 

 111. ; 6, the Tinamous (Tinamus, Lath., Cryptwus, 111., Ynambm, 

 D'Azara). Of this last sub-genus Cuvier remarks that some, thePezus 

 of Spix, have still a small tail hidden under the feathers of the 

 rump ; others, the Tinamui of Spix, have no tail at all, and their 

 nostrils are placed a little farther backward ; and he adds that one 

 should distinguish Rhynchotus of Spix, which has the bill stronger, 

 without any furrow, slightly arched and depressed, with the nostrils 

 pierced towards its base. 



Mr. Vigors places the Tetraonidai among the Itasores, observing that 

 the groups which form the family are chiefly distinguished in modern 

 systems from those of the Phasianidw by their more simple appear- 

 ance ; by the absence hi fact of those ornaments to the plumage, and 

 those naked or carunculated appendages to the cheeks and head, so 

 conspicuous in the latter family, but which are reduced in the present 

 to the mere space that encircles the eye. 



Mr. Swainsoa thus defines the " Tetraonidce., Partridges and Grouse : 

 Bill and tail very short; hallux elevated ;" and he comprises under 

 the family the following genera and sub-genera : 



Cryptonyx, Temm. ; Odontophorus, Vieill. ; Ortygis, 111. ; Tetrao, 

 with the sub-genera Tetrao, Linn., Lagopus, Willughby, Lyrurus, Sw., 

 Pterocles, Temm., and Centrocercus, Sw. ; Perdix, Briss., with the sub- 

 genera Perdix, C/uetopus, Sw., Cotarnix, Briss., Ptilopachus, Sw., and 

 Ortyx, Steph. ; Crypturus, 111., with the sub-genera Crypturus and 

 Nothurus, Wagl. 



Prince Bonaparte makes the Gallince the third order of his second 

 sub-class Grallatores ; and this order comprises the families Pleroclidce, 

 Phatianidce, Tetraonid(e, and Crypturidce. The order next in succession 

 to the Gallince is formed by the Grallce. 



Mr. G. R. Gray, in his ' List of the Genera of Birds,' arranges the 

 Tetraonidce between the Phasianidce and the Ckionididte, with the 

 following sub-families and genera : 



1. Perdicince. 



Genera : R/iizothera, G. R. Gray ; Ptilopachus, Sw. ; Mtagiiiis, 

 Wagl. ; Lerwa, Hodgs. ; Plernisles, Wagl. ; Francolinus, Briss. ; Cha- 

 cura, Hodgs. ; Perdix, Antiq. ; Arborophila, Hodgs. ; Coturnie, Autiq. ; 

 Rollulus, Bonn. ; Odontophorus, Vieill. ; Ortyx, Steph. ; Lophorty.c, 

 Bonap. ; Callipepla, Wagl. 



2. letraonina. 



Genera : Tetrao, Linn. ; Lyrurus, Sw. ; Eonasu, Briss. (Bonasia, 

 Bonap.) ; Cenlrocercus, Sw. ; Lagopus, Briss. 



3. Pteroclince. 



Genera : Pterocles, Temm. ; Syrrhaptes, 111. 

 The following species are European : Tetrao Uroyallus, the Capercail- 



