These, however, have often protected them from the competition of more vigorous invading races. Fagus, starting from the northern hemisphere, has more than held its own in Europe and Asia, but has all but died out in North America, finding conditions favourable for a fresh start in Australasia. The older types of Gymnosperms are inelastic and dying out. Even Pinus has found the task of crossing the tropics insuperable.
The whole story points to a general distribution of flowering plants from the northern hemisphere southwards. It confirms the general belief on geological grounds that this was the seat of their development at the close of the Mesozoic era. It is certain that they originally existed under warmer conditions of climate than now obtain, and that progressive refrigeration has supplied a powerful impulse to migration. The tropics eventually became, what they are now, great areas of preservation. The Northern Temperate region was denuded of its floral wealth, of which it only retains a comparatively scanty wreck. High mountain levels supplied paths of communication for stocking the South Temperate region, the floras of which were enriched by adapted forms of tropical types. Such profound changes must necessarily have been accompanied by enormous elimination, the migrating hosts were perpetually thinned by falling out on the way. Further development was, however, not stopped, but in many cases stimulated by migration and settlement in new homes. The northern Quercus, arrested at the tropic in the new world, expanded in that of the old into new and striking races. And it cannot be doubted that the profusion of Melastomaceae in South America was not derived from elsewhere, but the result of local evolution. There is some evidence of a returning stream from the south, but as Hooker and A. de Candolle have pointed out, It is insignificant as compared with the outgoing one Darwin attributes this to the fact that “the northern forms were the more powerful” (Origin of Species, 5th ed, p. 458).
The result of migration is that races of widely different origin and habit have had to adapt themselves to similar conditions. This has brought about superficial resemblance in the floras of different countries. At first sight a South African Euphorbia might be mistaken for a South American Cactus, an Aloe for an Agave, a Senecio for ivy, or a New Zealand Veronica for a European Salicornia. A geographical botany based on such resemblances is only in reality a study of adaptations. The investigation of these may raise and solve interesting physiological problems, but throw no light on the facts and genetic relationship which a rational explanation of distribution requires. If we study a population and sort it into soldiers, sailors, ecclesiastics, lawyers and artisans, we may obtain facts of sociological value but learn nothing as to its racial origin and composition.
In the attempt that has been made to map out the land surface of the earth, probable community of origin has been relied upon more than the possession of obvious characters. That sub-regions framed on this principle should show interrelations and some degree of overlapping is only what might have been expected, and, in fact, confirms the validity of the principle adopted. It is interesting to observe that though deduced exclusively from the study of flowering plants, they are in substantial agreement with those now generally adopted by zoologists, and may therefore be presumed to be on the whole “natural.”
Authorities—A. de Candolle, La Géographie botanique raisonnée, (Paris and Geneva, 1855); A Grisebach, La Végetation du globe, transl. by P. de Tchihatchef (Paris, 1875); Engler, Versuch einer Entwicklungsgeschichte der Pflanzenwelt (Leipzig, 1879–1882); Oscar Drude, Manuel de géographie botanique, transl. by G. Poirault (Paris, 1897), A. F. W. Schimper, Plant Geography, transl. by W. R. Fisher, (Oxford, 1903). (W. T. T.-D.)
PLANUDES, MAXIMUS (c. 1260–1330), Byzantine grammarian
and theologian, flourished during the reigns of Michael VIII.
and Andronicus II. Palaeologi. He was born at Nicomedia
in Bithynia, but the greater part of his life was spent in
Constantinople, where as a monk he devoted himself to study
and teaching. On entering the monastery he changed his
original name Manuel to Maximus. Planudes possessed a knowledge of Latin remarkable at a time when Rome and Italy
were regarded with hatred and contempt by the Byzantines.
To this accomplishment he probably owed his selection as one
of the ambassadors sent by Andronicus II. in 1327 to remonstrate
with the Venetians for their attack upon the Genoese settlement
in Pera. A more important result was that Planudes, especially
by his translations, paved the way for the introduction of the
Greek language and literature into the West.
He was the author of numerous works; notably a Greek grammar in the form of question and answer, like the Έρωτήματα of Moschopulus, with an appendix on the so-called “political” verse; a treatise on syntax; a biography of Aesop and a prose version of the fables, scholia on certain Greek authors; two hexameter poems, one a eulogy of Claudius Ptolemaeus, the other an account of the sudden change of an ox into a mouse; a treatise on the method of calculating in use amongst the Indians (ed. C. J. Gerhardt, Halle, 1865); and scholia to the first two books of the Arithmetic of Diophantus. His numerous translations from the Latin included Cicero’s Somnium Scipionis with the commentary of Macrobius; Caesar’s Gallic War; Ovid’s Heroides and Metamorphoses; Boetius, De consolatione philosophiae; Augustine, De trinitate. These translations were very popular during the middle ages as textbooks for the study of Greek. It is, however, as the editor and compiler of the collection of minor poems known by his name (see Anthology: Greek) that he is chiefly remembered.
See Fabricius, Bibliotheca graeca, ed. Harles, xi. 682; theological writings in Migne, Patrologia graeca, cxlvii; correspondence, ed. M. Treu (1890), with a valuable commentary; K. Krümbacher, Geschichte der byzantinischen Litteratur (1897); J. E. Sandys, Hist. of Class. Schol. (1906), vol. i.
PLAQUE, a French term for a small flat plate or tablet, applied particularly to rectangular or circular ornamental plates or tablets of bronze, silver, lead or other metal, or of porcelain or ivory. Small plaques, plaquettes, in low relief in bronze or lead, were produced in great perfection in Italy at the end of the 15th and beginning of the 16th centuries, and were usually copies of ancient engraved gems, earlier goldsmith work and the like.
PLASENCIA, a city of Spain and an episcopal see, in the north of the province of Caceres. Pop. (1900), 8208. Plasencia is situated on the river Jerte, a subtributary of the Tagus, and at the foot of the sierras of Bejar and Vera. The place has some interest on account of its fine walls, built in 1197 by Alphonso VIII. of Castile, and its cathedral, begun in 1498, a favourable specimen of the ornate Gothic of its period. The Hieronymite convent of Yuste, the scene of the last years of the emperor Charles V. (1500–1558), is 24 m. east.
PLASSEY (Palāsi), a village of Bengal on the river Bhagirathi,
the scene of Clive’s victory of the 23rd of June 1757,
over the forces of the nawab Suraj-ud-Dowlah. The fall of
Calcutta and the “Black Hole” atrocity led to instant action
by the East India Company, and Clive, with as many troops as
could be spared, undertook a campaign against the nawab, and
soon reoccupied Calcutta. Long and intricate negotiations,
or rather intrigues, followed, and at the time of the battle the
loyalty of most of the nawab’s generals had been effectually
undermined, though assistance, active or passive, could hardly
be counted on. With this doubtful advantage, Clive, with
1100 European and 2100 native soldiers, and 10 field-pieces,
took the field against the nawab, who had 50,000 men, 53 heavy
guns, and some French artillery under M. de St Frais. Only
the river Bhagirathi separated Clive’s little force from the
entrenched camp of the enemy, when the English leader, for
once undecided, called a council of war. Clive and the majority
were against fighting; Major Eyre Coote, of the 39th Foot, and
a few others for action. Coote’s soldierly advice powerfully
impressed Clive, and after deep consideration he altered his
mind and issued orders to cross the river. After a fatiguing
march, the force bivouacked in a grove near Plassey early on
the 23rd. The nawab’s host came out of its lines and was
drawn up in a huge semicircle almost enclosing the little force
in the grove, and St Frais’ gunners on the right wing opened
fire. Clive replied, and was soon subjected to the converging fire
of 50 heavy guns. For hours the unequal fight was maintained,
