March 31, 19 10] 



NATURE 



123 



jng this volume. It is, we believe, the first treatise 

 in English which has fully utilised the remarkable 

 archaeological discoveries of the last decade in 

 Mediterranean countries, and the author is to be 

 congratulated on the thoroughness and ability with 

 which he has accomplished his task. J. G. 



BOTANICAL PHOTOGRAPHS. 

 Vegetatiottsbilder. Seventh series. Parts iii. to viii. 

 Part iii., Der nordliche Schwarzwald, by Otto 

 Feucht; part iv., Vegetationsbilder aus Dalmatien, 

 by L. Adamovic; part v., Charakterpflanzen des 

 abessinischen Hochlandes, by Felix Rosen ; parts 

 vi. and vii., Pflanzenformationen aus Ost-Bolivia, 

 by Th. Herzog; part viii., Vegetationsbilder aus 

 Danisch-Westgronland, by M. Rikli. Price 4 marks, 

 each part contain^pg 6 photographs. Edited by 

 Prof. G. Karsten and Prof. H. Schenck. (Jena : 

 Gustav Fischer, 1909-10.) 



THIS unique botanical publication is being continu- 

 ally extended, so that a seventh series is now 

 jmpleted. The first double part of the volume, deal- 

 ing with the colonisation of volcanic lands in Java and 

 Sumatra, has been previously noticed. The third part is 

 devoted to the vegetation of the northern area of the 

 Black Forest, which is characterised by its coniferous 

 trees and moorland. A typical bit of high moor shows 

 bushes of Pinus montatia, clumps of Scirpus caes- 

 pitosus and tufts of Jiincus squarrosus. On another 

 plate the same pine is seen as a tall tree, contrasting 

 with the adjacent Scots pine and spruce. The author 

 has also been verj' successful with his representations 

 of the two subalpines, Andromeda poUfolia and 

 Athyriiim alpestre, and of the umbellifer, Meum 

 4xthamauticiim. Dr. L. Adamovic has brought to- 

 gether a most attractive set of photographs from the 

 sunny climate of Dalmatia. They illustrate a strip 

 of shore and rocks of the littoral, sublittoral and mon- 

 tane regions. So carefully have the spots been chosen 

 and the photographs taken that the author can point 

 out most of the individual plants. Especially charm- 

 ing is the first plate, showing Aster Tripoliutn with 

 species of Statice and Inula crithtnoides on the shore, 

 and the second picture of sublittoral rock where 

 Dianthiis dalmaticus and Iris germanica, with other 

 plants, are easily recognised. Trees provide the chief 

 feature of the views on the Abyssinian plateau. The 

 rosaceous plant Hagenia abyssinica, which tardily 

 assumes its arboreal sh^pe, is very striking ; the unripe 

 fruits are esteemed by the natives as a valuable 

 specific for internal complaints. A fine specimen of 

 tree Euphorbia is depicted, which the author suggests 

 may have developed an arboreal form when it passed 

 from a dn,- to a moist climate. Even more singular 

 is the tree Lobelia, formerly known as Rhyncho- 

 petalum. Illustrations are also given of a huge 

 spreading Ficus and a tree Entada. 



Dr. Th. Herzog has provided a fine double part 

 relating to the remote territon,' of East Bolivia. Along 

 the Paraguay, on savannah land subject to inundations, 

 IS the home of the wax palm, Copernicia cerifera, 

 where it is associated with tall grasses, species of 



I Paspalum and Andropogon. Another plate represents 



I NO. 2109, ^'C>L. 83] 



the growth of the palm Acrocomia Total, on the sand- 

 stone highlands of Chiquitos. A " monte " or thicket 

 formation occurs on parts of the plain of the Rio 

 Grande, where thorny scrub and succulents predomi- 

 nate ; the plates depict species of Cereus, a 

 Trithrinax and the bromeliad Aechmea polystachya, 

 which last is valuable to travellers, as it generally 

 holds a store of water. Other palms selected for 

 illustration *are Orhignya palmata and Mauritia 

 vinifera, typical of the savannahs, Astrocaryunt Chonta 

 and Iriartea exorrhiza, denizens of the rain forests; 

 Iriartea produces remarkable thorny prop roots. The 

 last two plates portray succulents, of which Pilocerens 

 celsianus is the most striking, on account of its 

 silvery crown of hairs. 



The concluding part contains some t\"pical aspects 

 of vegetation in Danish West Greenland. In the 

 southern area birches alone attain to the height of 

 trees as seen in the first plate ; the second indicates 

 the importance of Salix glauca. A brilliant photo- 

 graph of an Arctic meadow would be better appre- 

 ciated if a key to the plants had been supplied. There 

 is an effective photograph of cotton-grass growing 

 by the edge of a lake, and another of clumps of 

 Glyceria distans which attract attention on account of 

 the f)eculiar lie of the stems. 



MAOyETIC CHARTS. 

 Magnetische Kartographie in historisch-kritischer 

 Darstellung. By G. Hellmann. Veroffentlichungen 

 des Kg. Preuss. Meteorologischen Instituts, Ab- 

 handlungen, Bd. iii., Nr. 3. Pp. 61. (Berlin : 

 Behrend and Co., 1909.). Price 6 marks. 



DR. G. HELLMANN, as head of the Prussian 

 Meteorological Institute, which controls the 

 magnetic observaton,- at Potsdam, and as a lover and 

 collector of antique magnetic literature, is con- 

 spicuously qualified for the work he has undertaken 

 in the present volume. It aims at giving a complete 

 list of all magnetic charts of anj^ importance. All 

 time prior to the year 1700 is regarded by Dr. 

 Hellmann as preceding the era of charts, but he 

 devotes a few pages to Columbus and other pioneers, 

 whose work relates to the discover}* that the magnetic 

 needle is usually inclined to the geographical meridian. 



Time since 1700 is divided into two periods. The 

 first, extending until 1835, was heralded in by the 

 famous chart of Halley ; it is briefly discussed on 

 pp. lo-ii. The second period, extending from 1835 

 to the present day, saw the introduction of magnetic 

 surveys on land. 



The earliest work of this kind, according to our 

 author, took place in England on the initiative of the 

 British Association. On pp. 11-17 there is an 

 enumeration of all the principal land sur\'eys; while 

 pp. 18-27 summarise the present state of our know- 

 ledge of the distribution of the magnetic elements. 

 There is a useful list on p. 26 of the epochs of the 

 principal sur\'eys since 1891, with particulars as to 

 the number and density- of distribution of the stations. 

 A number of propositions are laid down in pp. 28-29 

 as to the objects to be aimed at in magnetic surveys 

 and other work preliminary- to the construction o£ 



