136 



SCIENCE-GOSSIP. 



CONTRIBUTED BY G. K. GUDE, F.Z.S. 



La Feuille des Jecnes Naturalistes (Paris, 

 September, 1896). Dr. E. Fournier contributes an 

 interesting and instructive article on " Geographic 

 Botany," in which he deals with the zones of vege- 

 tation of the Caucasus. This mountain chain does 

 not constitute, from a botanical point of view, a 

 t3-pical province, in which differences of altitude 

 only influence the distribution of plants. Present- 

 ing over its whole extent a great variety of climate, 

 it furnishes consequently a large number of biological 

 divisions, each characterized by special groups of 

 species. These divisions are, going from west to east : 

 the Black Sea district, the "Western Transcaucasian 

 district, East Imeritia, Georgia, and Khakhetia ; the 

 European Steppes district, the Asiatic Steppes dis- 

 trict and the Saline Steppes district. Independently 

 of these divisions, five principal zones of altitudinal 

 distribution may be distinguished : Inferior zone 

 to goo metres, in which many exotic plants are 

 cultivated ; zone of the beech and chestnut, from 

 goo to 1,500 metres; zone of the conifers, from 

 1,500 to 2,000 metres ; Sub-Alpine zone, from 2,000 

 to 3,000 metres ; Alpine zone, from 3,000 metres 

 to the limit of vegetation, which is excessively 

 variable. The Alpine zone has many plants in 

 common over all the six divisions, such as Primula 

 grandis, two species of Campanula, Ge?itiana pyrenaica, 

 Veronica gentianoides, Myosotis sylvatica. Rhododendron 

 caucasica, and others. The Sub-Alpine zone also has 

 several plants in common over the six divisions, 

 birch, stunted beech. Daphne, Viburnum lantana, 

 Sorbus aria, and others. The Conifer zone has 

 Picea orientalis and Abies nordmanniana distributed 

 over the first three divisions, the Black Sea 

 Province, "Western Transcaucasia, and the Imeritia 

 District ; while in the Eastern Caucasus, forming 

 the three Steppes divisions, the Conifers are 

 replaced by birches, except in Daghestan, v.here 

 sometimes forests of Pinus sylvestris are found. 

 In the beech and chestnut zone the differences 

 in distribution over all the divisions become 

 apparent, the first division, i.e. the Black Sea 

 Province, having, besides the two trees which give 

 its name to this zone, Pinus halepensis and Pinus 

 pinca ; the second district, Western Transcaucasia, 

 contains, besides beech and chestnut, alder, 

 oak, sycamore, Rhododendron ponticum, etc. The 

 Imeritia district has its forests of birch and chest- 

 nut much thinner, interspersed with rhododendrons 

 and azalea's ; the European Steppes division is 

 noted for Berberis, besides beech and chestnut, 

 while in the remaining two Steppes divisions 

 forests are very scarce. The inferior zone is most 

 differentiated, the Black Sea Province being noted 

 for Pinus halepensis, evergreen oaks, junipers and 

 an abundance of ^Mediterranean species ; the 

 Western Transcaucasian division contains mixed 

 forests, creepers, ferns, and a fair number of 

 Mediterranean species ; the Imeritian district pro- 

 duces Rhododendron ponticum, honeysuckle, paeonies 

 and some Mediterranean species ; in the European 

 Steppes district grasses, Chenopodiaceae, Legu- 



minosae, Labiatae and Artemisia abound ; the 

 .\siatic Steppes di\ision is rich in pasturage, and 

 produces Sternbcrgia jisheri and Helleborus caucasicus, 

 while the Saline Steppes district has Salsola, Arte- 

 misia, Euphorbia, fennel, etc. One of the most salient 

 points is the abundance of Mediterranean species in 

 the whole of Western and Central Transcaucasia ; 

 while a noteworthy fact is the presence, among the 

 species special to the Caucasian flora, of many 

 tj-pes with tertiary afhnit)-. These include Quercus 

 pontica, an oak with simple leaves similar to those 

 of a chestnut, Betula niediiedcvi, a birch with alder- 

 like leaves, forming the passage between the Asiatic 

 birches and an American species, Betula lenta. 

 Rhododendron ponticum has been found in the tertiary 

 beds of Austria ; and many others. M. Raspail 

 discourses on " Bird Migration by the aid of East 

 Winds." In a short illustrated article on the marsh- 

 otter or European minx, Mr. Anfrie refers to some 

 previous remarks made about the occurrence in 

 France of this animal (ante p. 51), and gives, 

 besides a woodcut, some further iniormation about 

 this interesting and little-known carnivore. 



Album der Natuur (Haarlem, i8g6. Parts i and 

 2). An appreciative account of the late Louis 

 Pasteur, with portrait, is contributed by Dr. H. P. 

 W"ijsman : while Dr. Tjaden Modderman discourses 

 on the life and works of the physicist, Thomas 

 Young, whose biography, by Peacock, w^as published 

 in 1890, by Mr. John Murray. Dr. Hugo de Vries, 

 in a note entitled " Species or Variety," discusses 

 the history of Chelidonium laciniatum, which is looked 

 upon as a species by some, as a variety of Cheli- 

 donium majus by others. It appears that a chemist 

 in Heidelberg, Sprenger by name, found, about the 

 year 1590, a new form of celandine in his garden ; 

 it was not found elsewhere, neither wild nor culti- 

 vated. Sprenger sent specimens to Bauhin, Clusius, 

 Plater and others, all of whom admitted it as a 

 nev,- plant. It was soon distributed in botanic 

 gardens in France, England, German}- and 

 Holland. Since then it has occasionally been 

 found as an escape, but has never been found 

 really wild. That this form is constant, has 

 been proved by cultivation ; IMiller raised it 

 from seed during forty successive years, with- 

 out ever noting the least reversion to the tj-pe. 

 On the other hand, the common celandine is 

 frequently sown on a large scale, j-et this phe- 

 nomenon, which presumably occurred in Sprenger's 

 garden, has never been again observed. If perfect 

 constancy and complete separation of two allied 

 types are considered sufficient characters to regard 

 both as distinct species, there can be no doubt that 

 the two forms in question are true species. The 

 writer of the article, witnout taking sides with 

 either view, considers that the facts stated are 

 of extreme importance to all who are interested 

 in the origin of species. Chelidonium laciniatum 

 behaves as a true species in giving rise to other 

 varieties. The degree of division of the leaves is 

 so variable .that three different varieties can be dis- 

 tinguished, the variety crenatum being intermediate 

 between the type and the variety fumariaejolium. in 

 which the division is carried so far that the leaflets 

 or pinnae are almost linear and very numerous. 

 But it was found that all the three forms were 

 obtained from seed of C. laciniatum. It was observed 

 that some plants passed through all the three stages, 

 beginning as var. crenatum and ending with the var. 

 fumariaefolium. None of the seedling plants ever 

 showed the least sign of reverting to the typical 

 form of C. majus. 



