Ill* 



TUBUL1PORA. 



TUNICATA. 



which corresponds with a similar ilit in the mantle which covers the 

 branchial cavity. Along the whole length of thin alit adheres a 

 branchial comb, composed of a great quantity of foliations, distinct 

 and, as it were, tubular. Linnaeus placed them with the Serpulrr, and 

 Cuvier observes that in these later times some have believed that they 

 belong to the class of Annelids. Thus Lamarck supposed fili'iuaria 

 as wefl as Vermiiia to be approximated to the Serpula. 



Seven recent and ten fossil species have been recorded. 



& mnrifala, a native of the Indian Seas, mtiy be taken as an 

 example. 



SiliqvaHa muricala. 



Species of this genus have been found in sponges. 



Mayilut. [MAOIU/S.] 



TUBULIPORA. (I'OLTZOA.1 



TUBULIPO'RAD^. [POLTZOA.] 



TUCUTUCO. [MuRiDJt] 



TUFF, or TUFA. The accumulations of scoria and uhes about 

 a volcanic crater, Which are re-aggregated so as to make a coherent or 

 solid man, are termed Volcanic Tuff Similar but more ancient aggre- 

 gations of the products of heat, re-aggregated into 6rm, solid, or even 

 highly compact rock, are called Trap Tuff. 



TULIP. [TULIPA.] 



TI''LIPA, a genus of Plants belonging to the natural order IMiactce. 

 Tliis name is a corruption of the Persian word Thoulyban, or Toleban, 

 which is the name the plants of this genus bear in Persia. The Persian 

 word also signifies a turban. The genus is known by its perianth 

 being composed of six sepals. The stigma is 3-lobed ; the seeds are 

 smooth, and it has neither nectary nor style. All the species are herba- 

 ceous plants, developed from a bulb ; the flowers are mostly solitary, 

 seated on a lengthened scape, at the base of which the leaves, not 

 numerous, are developed. About thirty species have been described. 



T. tylwtrii, the Wild Tulip, has the stem 1-flowered, somewhat 

 drooping; the leaves of the perianth ovate-acuminate, hairy at the 

 extremity, the stameui hairy at the base. This is the only species of 

 tulip that is a native of Great Britain. In England it occurs in the 

 counties of Norfolk, Suffolk, Hertfordshire, and Middlesex, in a chalk 

 oil It has also been found in Scotland. It is found in the southern 

 parts of Germany, in Switzerland, Italy, and France. It has yellow 

 flowers, and blooms in April and May. It increases itself by throwing 

 out a long stout fibre from its root, at the extremity of which a bulb 

 is developed, and thus a new individual is produced at a considerable 

 distance from the parent plant. 



T. (fcn/M&rfu, the Agcn Tulip, lias a 1 flowered glabrous stem; 

 oblongo-lanct olate leaves ; the stamens smooth ; the exterior leaves of 

 the perianth acuminate, the inferior onea obtuse. This species was 

 not known to Llnmcun, and was first distinguished by St. Amans. It 

 was found at Agen in Frano-. and also grows wild in Italy, Germany, 

 and other parts of Europe. The flowers are large and bell-shaped, of 

 a fine scarlet-red colour, each petal marked with a broad black yellow- 

 edged spot at iU base. It blossoms in April and May. 



T, ntartolrnt, the Early Dwarf, or Van Thol Tulip, Is a native of 

 the south of Europe. It blooms in March and April. 



T. Ctlticma, Small Yellow Tulip, has a solitary, mostly erect, flower; 

 the leaves of the stem lanceolate ; leaves of perianth greenish, lanceo- 



late ; the stamens slightly hairy above the base. This plant blossoms 

 in March or April, and is a native of the south of Europe, and of the 

 banks of the Volga. It was known to Clusius, Bauhin, Magnol, and 

 Tournefort, but Linnieus confounded it with the wild tulip. 



T. Clutianoj Red and White Italian Tulip. Thii tulip was con- 

 founded by I.inuEOUs with the T. Grtneriana. 



T. birtora, the Two-Flowered Yellow Tulip, is a native of the rait 

 deserts about the Volga, and is found in company with T. Velnana. 

 The flowers are fragrant. 



T. Gemeriana, Common Garden Tulip, has the stem 1-flowered and 

 smooth, as well as the petals and filaments ; the flower erect, the 

 leaves ovato-lanceolate, glaucous and smooth ; the lobes of the stigma 

 decurrcnt and deeply divided. Of all the species of tulip this one is 

 the best known, and has perhaps had more attention bestowed upon 

 it than any other plant that produces only flowers. ThU specie* of 

 tulip grows wild in the Levant, and appears to have been cultivated 

 by the Turks in their gardens from an early period. 



The Tulip was first introduced into France in 1611. It does not 

 appear at what time it was first carried to Holland, but the Dutch 

 were early in the habit cf sending to Constantinople for tulip-seeds. 

 It was in this country that the Tulip was destined to make the greatest 

 impression. In the early part of the 17th century the passion for the 

 possession of these plants became so strong, that dealing in them become 

 one of the most important money speculations, and the bulbs of tulips 

 were sold and resold at enormous prices, in the same manner as stocks 

 are on the Stock Exchange of England. It became in fact a gambling 

 transaction, in which persons ventured their capital, in the hope that 

 particular kinds of tulips would realise a higher price. This practice 

 was not carried on throughout Europe, but was confined to the Nether- 

 lands, and rose to its greatest height in the years 1634, 163.V 

 1637. Beckmann, in his ' History of Inventions,' gives an account of 

 this remarkable tulipomauia, as it was called. One variety of tulip, 

 called the Viceroy, was exchanged for articles valued at 2500 florins. 

 [Tour, in ARTS AHD Sc. Div.] 



TULIP-TREE. [LIRIODKNDROK.] 



TUNGSTEN, a Metal It was first obtained in its pure state in 

 1781. Its name is derived from ' tung sten,' two Swedish words, 

 Dignifying ' heavy stone,' from the weight of its ore. It is also called 

 Scheelite, in honour of the chemUt Scbeele. 



Tungsten is found in combination with iron, lead, and lime, con- 

 stituting Wolfram, Tungstate of Lead, and Tungstate of Lime. It 

 also occurs sparingly in some ores of columbium, as iu certain varieties 

 of the minerals pyrochlore, columbite. and yttro-columbite. It is 

 met with in very small quantities as an ochre, or as tungstic acid, 

 forming a yellow powder on other Tungsten ores. 



No use in the arts has been made of this metal or its compounds. 

 Tungstic acid is a fine yellow, even brighter than chrome yellow, but 

 it turns green on exposure to the sun's rays. 



Tungstate of Lime occurs in square octahedrons. Cleavage octa- 

 hedral, perfect Colour yellowish-white or brownish. Brittle. Ha; 

 4 to 4 - 5. Specific gravity 6-075. It is composed of Tungstic Acid 7'8; 

 Lime 19'06. Infusible alone, or only, on the thinnest edges. 



TUNICA'TA, a family of Acephalous Mollutca. The following 

 graphic description is given of these interesting forms of animal life 

 in Forbes and Hanley's 'British Mollusc;*': " Rarely is the dredge 

 drawn up from any sea-bed at all prolific in submarine creature*, 

 without containing few or many irregularly-shaped leathery bodies, 

 fixed to sea-weed, rock, or shell, by one extremity or by one side, 

 free at the other, and presenting two more or less prominent orifice*, 

 from which, on the slightest pressure, the sea-water is ejected with 

 great force. On the sea-shore when the tide is out, we find similar 

 bodies attached to the under surface of rough stones. They are vari- 

 ously, often splendidly coloured, but otherwise are unattractive, or even 

 repulsive in aspect. These creatures are Atcidia properly so called. 

 Numbers of them are often found clustering among tangles, like 

 branches of some strange somitransparent fruit. They are very apa- 

 thetic and inactive, living upon microscopic creatures drawn in with 

 currents of water, by means of their ciliated respiratory organs. The 

 leathery cue is often encrusted with stones and shells, decorated with 

 parasitical though ornamental plumes of corallines, and not seldom 

 perforated by bivalve*, which lodge themselves snugly in the tough 

 but smooth skin. It is the analogue of the true shell of conchiferous 

 Moltiuca. It is a sac, closed except at two orifices, one of which is 

 branchial, the other anal. This elastic, gelatinous, or coriaceous enve- 

 lope is called the test, and incloses a second tunic or mantle, which is 

 muscular, and adheres to the first only near the orifices. The branchial 

 ROC lines the interior of the mantle in pint ; it in both respiratory and 

 pharyngeaL The remainder of the cavity h occupied with the prin- 

 cipal organs of digestion, circulation, and generation. The chief 

 nervous centra is situated between the two openings of the muscular 

 tunic. The sexes of Aiciditc are distinct." For our present know- 

 ledge of the structure and relations of these animals we are greatly 

 indebted to Savigny. They were not however unknown to Aristotle. 

 In the ' Historia Animalium,' he observes, under the head of 

 Testaceous Animals (TO 'Oarfv<6Stptui), that " there are some, such as 

 those called T^ffva, which are so entirely surrounded by their test or 

 envelope a* to have no part of their flesh exposed." So far, ax 

 Mr. M'Leay remarks, this accurately drawn character may apply to 



