490 



NATURE 



[June 8, 191 1 



'1 liese sandstones are unfossiliferous, and an abso- 

 lute proof of their Eocene age must accordingly be 

 wanting; but, jaiiie dc mictix. Dr. Falconer makes 

 out an excellent case and presents his facts clearly. 



The book concludes with chapters on "The Super- 

 ficial Accumulations," " Tertiary Crustal Movements," 

 and "Tertiary Volcanic .Action," each worthy of the 

 dose attention of the student of African geology. Two 

 periods of Tertiary volcanic activity are recognised, 

 respectively middle Eocene and late Pliocene; to the 

 latter are referred some excellently preserved puys 

 (Fig. 2) developed in the Province of Yola, the middle 

 Henue valley and on the Bauchi plateau. 



The rocks of the earlier outburst are an interesting 

 series of phonolites and nepheline-basalts, of which 

 the conspicuous stumps of the Tangale Peak and the 

 Wase rock may be taken as typical examples. 



In regard to the late earth movements, one conclu- 

 sion of general interest may be recorded here, viz., 

 that the culmination of the Tertiarv oscillation resulted 



Fig. 2.— Craters in the Mboi Hills. From "The Geology and Geography of Northern Nigeria 



m the formation of the Bauchi plateau and the estab- 

 lii-hment of the present river system. 



The Bauchi district is inseparably connected with 

 the tin industry, and we could wish that Dr. Falconer 

 had seen his way to more details, put in plain and 

 concise phraseology, of the alluvium-containing cassi- 

 terite. 



The sudden prominence into which the tin-mining 

 industry has burst in northern Nigeria naturally leads 

 the reader, in such a work as this, to expect authori- 

 tative information in a form to be readily assimilated. 



Mr. Henry Woods has contributed an appendix on 

 the palaeontology, and the book as a whole is full of 

 valuable information to the student; the geological 

 map on a scale of i : 2,000,000 is indispensable to those 

 interested in the structure of this part of Africa. 



.\s Dr. Falconer himself readily admits, his work 

 may require some modification in the future, but all 

 who are acquainted with the difficulties of the African 

 pioneer will give him full measure of praise for the 

 results he has attained. In such circumstances to 

 quibble over detail is an ill task, but the first chapter 

 on the " Physical Geography " might be compressed 

 and summarised with advantage to the general reader, 

 and perhaps many will find a too great elaboration of 

 detail throughout the work. John Parkinson. 



NO. 2 1 71, VOL. 86] 



DR. HARRY BOLUS. 

 nPHE name of Dr. Harry Bolus is closely associated 

 *■ with the story of South .African botany for the 

 last forty years. In .April, 1874, a letter to Sir Jom ph 

 Hooker was read at a meeting of the Linnean Soci* t\ . 

 of which Bolus had recently been elected a fellow 

 (December 18, 1873), in which he criticised Gris<rbacli\ 

 limitation of the Cape and Kalahari floral provinces 

 (see Journ. Linn. Soc., xiv.). This was the begin- 

 ning of a series of publications embodying the results 

 of his observations on the flora of a peculiarly rich 

 and attractive botanical area. In 1886 Bolus wrote 

 for the official handbook of the Cape of Good Hope 

 a valuable "Sketch of the Flora of South Africa." 

 in which he proposed a series of natural botanical 

 divisions, forming, roughly, successive zones from the 

 coast northwards. From 1881 to 1889 he communi- 

 cated to the Linnean Society a number of contribu- 

 tions to South .African botany, containing critical notes 

 on various genera and species, as well as descriptions 

 of many novelties ; but it was 

 to the heaths and orchids that 

 he was especially devoted. The 

 results of his study of the large 

 and intricate genus Erica are 

 found in his monograph (in 

 part of which he had the help 

 of the late Prof. Guthrie) in 

 the "Flora Capensis " (vol. iv., 

 sect. I, issued in 1905), where 

 the 469 species are described in 

 detail, and arranged under 

 forty-one section-^. 



In his voluni. >outh 



African orchids, Dr. Bolus has 

 established a model of detailed 

 description and illustration ; 

 accompanying each .species is a 

 plate, drawn by Dr. Bolus him- 

 self, in which a judicious com- 

 bination of outline and colour 

 gives exactly what is wanted 

 by the botanical student. Dr. 

 Bolus had just completed this 

 important work at the time of 

 his death, which occurred on 

 May 25, when on a visit to 

 England. Mention should also 

 be made of the excellent series of specimens illustrat- 

 ing the Cape flora, by the distribution of which to 

 various great herbaria Dr. Bolus brought his col- 

 lections within reach of a large number of students of 

 systematic botany. An account of his senices to botany 

 would be incomplete without a reference to his generous 

 support of the Cape University, which owes to him 

 the foundation of its chair of botany; and Dr. Bolus 

 himself would have wished some acknowledgment 

 to be made of the help which he received in all his 

 later work from his niece and pupil, Miss Louisa 

 Kensit. A. B. R. 



NOTES. 



The Croon ian lecture of the Royal Society will be 

 delivered on June 15 by Prof. T. G. Brodie, F.R.S., on 

 " A New Conception of the Glomerular Activity." 



On Tuesday, June 13, Prof. Ernst Cohen, of the Uni- 

 versity of Utrecht, will give an illustrated lecture before 

 the Faraday Society on " Allotropic Forms of Metals." 

 Prof. T. W. Richards, of Harvard College, has been 

 invited to take the chair on this occasion. .Applications 

 for tickets should be made to the secretary, 82 \'ictoria 

 Street, London, S.W. 



