i :: >:r v i:.r. 



PROTEIN. 



Anthr adnat* with the Calyx. FnaMeatdia. 



Dehittcnt Frail 

 Unilocular. 



... Tary Iod*d Antiitr-'r, Grrrillca, IMea, Lambrrtia, 

 Xy'omtlum, Orilet, Kofula. 



Ovary i *eded. Ki<j/>lta. 



Ovary many -icedcd. Embothriuni, Ortocallii, Telopa, 

 lomaJi'a, Staoearpiu. 



* BUocuUr. Bauttia, Vryandra. 



A great many of UICM genera are named afUr botanists and patrons 



.VirnNi wa named in honour of Mr. Jame* Niven, an intelligent 

 I otanict, to whom we are indebted for tlie discovery of many new 

 peciei of South African plant*. Simna wai named after Dr. John 

 Sim*. for many yean editor of tlie ' Botanical Magazine. Frank- 

 lamdia WM named in honour of Sir Thoina* KrankUnd, Bart, who 

 haa atudied very succeasfully the submarine flora of this country. 

 I'rnwmia wa named by Sir J. S. Smitli afUr C. H. Pcrsoon, who 

 wrote aereral papers on Cryptogamio Botany, and published a com- 

 plete edition of the ' Systema Vegetabilium' of Linmcua. Beilendena, 

 named afttr John Bellenden Ker, who tun published many valuable 

 paprn on botany in the Annal* of Botany,' and the ' Botanical 

 Magazine.' OrtrilUa was named by Brown in honour of the right 

 honourable Charles Francis OreTille, a lover of natural history, and 

 formerly a vioe-pre*ident of the Royal Society. This name will also 

 be always associated by every botanist with that of Dr. Greville of 

 Edinburgh, the author of the ' Scottish Cryptogamic Flora. 1 Lamberlia 

 was named by Smith in honour of A. B. Lambert, a good botanist 

 and a distinguished patron of the science of botany. Knightia is a 

 prnus which was discovered by Sir Joseph Banks, and, at his sugges- 

 tion, named by Brown in honour of Thomas Andrew Knight, author 

 of many valuable papers on various departments of vegetable physi- 

 ology. Banl-iia was named by the younger Linnceus in honour of Sir 

 Joseph Banks. Drvandra, a genus closely allied to Banttia, was named 

 in honour of Mr.'Dryander, a Swede, librarian to Sir Joseph Banks, 

 and a learned and talented botanist. 



The geographical distribution of these plants is interesting. They 



nre almost entirely confined to the southern hemisphere, an observa- 



tion first made by Mr. Dryander. Their diffusion ia very extensive in 



this hemisphere, nor merely in latitude and longitude, but also in 



elevation. They cover not only the larger southern continents, but 



nre also found in New Zealand and New Caledonia ; but they have not 



hitherto been found in Madagascar or the lesser islands of the South 



Seas. In America they have been found in Tierradel Fuego, in Chili, 



in Peru, and even Guyana, The American species have more affinity 



with those of Australia than of Africa. It may be inferred that this 



family of plants U diffused over Africa, as they are abundant at the 



Cape of Good Hope, and Bruce found a genuine species of Prolea in 



Abyssinia. Wherever the shores of Australia have been explored, an 



abundance of Proteaceous Plants have been found, the great mass of 



the order existing here in about the name latitude as the Cape of 



Good Hope. On the south-west coast of Australia this order forms a 



much more decided feature of the vegetation than on the cast From 



the parallel of the mass the order diminishes in both directions, but 



the diminution towards the north appears to be more rapid on the 



nut than on the west coast. The most numerous genera are those 



which are the most widely diffused. Orevillea, Hakta, lianl-tia, and 



/Vrooma contain the largest amount of specie*, in the order in which 



they are mentioned, and are found spread nearly in the same propor- 



tion. Those genera which conaitt of one or very few species, and 



which exhibit the most remarkable deviations from the structure ol 



the order, are the moat local, and are found either in the principal 



parallel or in the highest latitude. The range of the specie* of the 



order it very limited, and there baa been no instance recorded of a 



pecie* of this family common to the eastern and western shores ol 



Australia. Ilanltia intryn/olia is probably the moat widely extended 



specie* ; but although it* range of latitude is very considerable, its 



rxtension in longitude is very small 



None of the plant* belonging to the natural order I'roleactct are 

 remariul.il- for their medicinal properties. The fruit of a specie* of 

 the genus Gutriua i* said to be sold in the market* of Chili under the 

 MOM of Arellano. At the Cape of Good Hope the plant* of this order 

 are most frequently made use of a* fire-wood. For this purpose the 

 dry woody character of their leave* peculiarly fit* them. They are 

 moat of them handsome evergreen shrub*, and are much prized by 

 gardroers, and form a part of every good collection of plant*. One 

 of the fio**t collections of thru plant* in this country U at the Royal 

 OardcM at Kew, where a great variety of this singular and interesting 

 group of plant* may be aeen. The genera most commonly fouii-l in 

 UiU country are QririUem, liauino. and //ryanc/ro. The fruit of the 

 Xflomrl** pjm/or, which the cut accompanying this article repre- 

 sent*, la very hard, and I* known in Australia under the name of 

 Wooden Pear. 



(Brown, ' On the 1'roUaowc of Juwieu,' in TO], x. of Linn. Tram. ; 

 Juanieu, art. 'ProUe*,' in DicHoitnairt da fvinca .Va'tti cllci ,- Bur- 

 nett, 0//i' o/ Botany; Lindlry, \alnral SgHtm.) 



PROTEIN (from rpvrttu, to rtand first), a substance first described 

 by Mulder, and obtained fiom animal and vegetable substances con- 

 taining nitrogen. Although the existence of Protein a* an independent 

 ub*Unoe haa been doubted, the theory of it* existence and it* relation 

 to animal and vegetable compound* generally has had the most ini- 



rtant influence on vegetable and animal physiology. It was through 

 . researches on Protein that Mulder came to the conclusion that 

 certain vegetable and animal compounds, a* fibrin, albumen, legumiu, 

 gluten, &c., were identical, and that these bodies are first formed in the 

 vegetable before they are appropriated by the animsL Liebig, who was 

 the first to adopt M ulder's views, now denies the independent existence 

 of Protein. Whether however this substance exist* as a chemical 

 compound or not, there can be no doubt of the close resemblance 

 in chemical composition and vital properties of albumen, fibrin, 

 and casein, and of their elements being united in the relations in 

 which they are represented in the formula for Protein. 



This substance was obtained by Mulder from Albumen, Casein, 

 Horn, and Animal and Vegetable Fibrin. When any one of these is 

 dissolved in a solution of potash, and the filtered solution is mixed 

 with a slight excess of acid, a copious grayish-white flocculent preci- 

 pitate is formed, and a slight smell of bydrosulphuric acid is perceived. 

 This white substance is Protein, so called from ita occupying the first 

 or most important place in relation to the albuminous principles. 



It* properties are : While moist the white flocculi are diaphanous, 

 but by drying they become yellowish, hard, and brittle. It possesses 

 neither smell nor taste, attracts moisture rapidly from the air, and 

 loses water at 212. It is insoluble in water, alcohol, ether, and 

 essential oils. By long continued boiling in water it undergoes some 

 change of properties, and is rendered soluble. 



Acetic and phosphoric acids, whatever may be their state of con- 

 centration, dissolve it ; hydrochloric acid also dissolves Protein, ami 

 acquires an iudigo tint When heated the solution blackens. With 

 concentrated sulphuric acid it produces a jelly which contract* in 

 water, and which, after being washed with water and alcohol, though 

 it does not redden litmus-paper, contains 8 -34 per cent of lulphnrio 

 acid. Mulder calls this compound Sulphoprotcio Acid. When Protein 

 is boiled in dilute sulphuric acid, it acquires a purple tint. 



Protein is precipitated from its acid solutions by the ferro- and 

 ferrid-cyanide of potassium, by tannin, and by neutralisation with an 

 alkali. When strougly heated, Protein is decomposed with the pro- 

 duction of ammonia and a charcoal which burns with difficulty, but 

 leaves no residue. , 



Protein consists entirely of carbon, hydrogen, nitrogen, and oxygen ; 

 and it will be observed, that whether obtained from Albumen (1), 

 Casein (2), Horn (3), Animal Fibi in (4), or Vegetable Fibrin (5), the 

 statements of its composition differ so slightly, as to show that it 

 must be the same from whichsoever of the sources named it ia 

 procured. 



(1) (2) (3) (4) (5) 



Carbon . . . 55'30 55-16 55-408 55-44 64-99 

 Hydrogen . . 6-94 7-1" 7'238 5'95 6-87 

 Nitrogen . . . 16-02 15-86 15'593 16-65 15'6(J 

 Oxygen . . . 21-34 21-81 21761 21-30 2248 



These analyses may be represented by C w H,, N, 0,,. 



Win n Protein, or the substances which yield it, are boiled in a con- 

 centrated solution of potash as long as ammonia is evolved, and the 

 solution is afterwards neutralised by sulphuric acid, evaporated to 

 drynesa, and the residue treated with boiling alcohol, threfe product* 

 of the decomposition are dissolved, one of which, Erythroprotide, 

 separates in oily drops as the solution cools ; Loucin is deposited in 

 small crystalline scales by spontaneous evaporation ; whilst the mother 

 water contains Protide nnd Formiatc of Ammonia in solution. 



Binoxide and Tritoxide of Protein are produced by the long con- 

 tinued action of boiling water upon fibrin in contact with air. They 

 are the chief ingredient* of the buffy coat of the blood in a state of 

 inflammation, being produced at the expense of the fibrin. 



Protein ii undoubtedly the most important of all known substances 

 in the organic kingdom. It is present in all parts of plants, in root', 

 items, leaves, fruit*, and in their several juices ; in the animal body 

 it is the chief constituent of the blood, the muscles, and many other 

 part*, and is the original source of numerous other compounds. In 

 plant* it assumes three different forms, being soluble in water, in- 

 soluble in water, or solublu in alcohol ; in animals it may be either 

 soluble or insoluble in water. It is one of the substances din-oily 

 prepared for the food of plants, and is found in the youngest roots ; 

 whether it is only formed there, and afterwards conveyed to the other 

 part*, or whether it is produced in any other part of the plant, is un- 

 certain. It* property of bcim; readily soluble in water facilitates it* 

 transference to the various o. ^ana. It may however assume the solid 

 state and become deposited in cells ; in this form it occurs in many 

 seeds, occasionally being their principal constituent. This deposition 

 is effected in a very simple manner. Most acids render it insoluble, 

 and therefore the mere presence of an acid is usually sufficient to 

 accomplish the transformation : again, the insoluble Protein may be 

 redUsolved by alkalies, and hence, after it has been deposited in the 

 cell* in a solid state, it may be removed to another part of the plant 

 through the medium of an alkaline solution. 



