December 22, 192 1] 



NATURE 



545 



tures were taken by Mr. Murphy, and his collections 

 are said to comprise practically the entire terrestrial 

 life of the Peruvian islands, together with geological 

 samples, a series of sea fishes, and invertebrates col- 

 lected during tow-net hauls in the Humboldt current. 

 Under the title of " Notes Relating to the Aboriginal 

 Tribes of the Eastern Province " Mr. I. Hewitt, in 

 the South African Journal of Science for 1920, dis- 

 cusses some relics of a pre-Bushman race. We have, 

 in the first place, stone implements which are sup- 

 posed to be analogous to those of the period of 

 Neanderthal man in Europe, though the question of 

 the age of the gravels in which they are found has 

 not been determined with certainty. Next come the 

 remains in the coastal districts, consisting of extensive 

 shell-mounds which are ascribed to the so-called 

 Strandloopers, who fed on shell-fish and other marine 

 products. In the course of this scholarly paper Mr. 

 Hewitt collects the historical data regarding the Hot- 

 tentots and Bushmen. From the craniological evidence 

 the coast population seems to have consisted of bastard 

 tribes containing Bushmen, Hottentot, and Kaffir 

 elements. One skull appears to resemble the " Proto- 

 ^:?yptian " t}pe described by Prof . Elliot Smith. This 

 if true, significant, because some authorities have 

 suggested on linguistic grounds a relationship between 

 the Hottentots and various northern pastoral tribes, 

 one of which, the Gallas, makes use of clicks. At 

 present the evidence in support of this theory is 

 scanty, but further investigations in South Africa mav 

 lead to the settlement of an interesting problem. 



The annual part of the Transactions of the Norfolk 

 and Norwich Naturalists' Society (vol. 11, pt, 2, 1921) 

 reflects in excellent manner the activities of this ad- 

 mirable local society. Mr. B. B. Riviere, the presi- 

 dent, leads off with a wealth of new observations to- 

 wards the solution of the hitherto rather mysterious 

 phenomenon of the daily autumnal migrations of gulls 

 on the Norfolk coast. The account is full of interest 

 and deserves wide publicity. Other bird papers in- 

 clude an attractive account by Mrs. Watson of the 

 methods used in the taking of a census of eggs of 

 the common tern on Blakeney Point, together with 

 notes on the nesting habits of these birds, and a short 

 authoritative statement by Dr. Sydney Long, the 

 secretary of the society, of what is being done towards 

 reorganising, correlating, and extending the measures 

 for bird protection in the county. On the botanical 

 side Mr. W^. G. Clarke and Mr. Robert Gurney con- 

 tribute a valuable study of the biology and distribu- 

 tion of the bladderwort (Utricularia), whilst Mr. 

 Clarke, in another article, revisits the botanical locali- 

 ties (for Norfolk) mentioned in Dawson Turner's 

 "Botanists' Guide through England and Wales " 

 (1805). The part closes with notes of local mterest 

 and with obituary notices. The number is in all re- 

 spects a valuable one. 



The researches of Prof. Hamburger, of Groningen, 

 on the permeability of cells have been of continuous 

 interest in their various developments since he inves- 

 tigated the laking of red corpuscles in dilute salt solu- 

 NO. 2721, VOL. 108] 



tions more than thirty years ago. A convenient sum- 

 mary and survey of the whole was given by him in a 

 lecture delivered at the University of London in June 

 last which appears in the Lancet of November 19- 

 That cells absorb some things from solutions and 

 fail to take up other substances is a well-recognised 

 fact. This has been attributed to a differential selec- 

 tive activity on the part of the living cell, closely 

 correlated with its physiological needs, the precise 

 psychological attitude of the cell varying with the 

 particular sort of neo-vitalism which advocates it. 

 Prof. Hamburger, on the other hand, premises a 

 purely physico-chemical problem, and urges with con- 

 siderable cogency that the intricacy and efficiency of 

 these processes is commonly under-estimated. He 

 shows, for example, how permeability may be altered 

 by changes in the conditions and environment ; carbon 

 dioxide profoundly modifies the permeability of red- 

 blood corpuscles and the permeability of the kidney 

 glomeri to sugar is entirely changed by alterations 

 in reaction of the liquid in which the sugar is dis- 

 solved. Emulsions, with which he thinks the boun- 

 daries of cells may fairly be compared, contain liquid 

 pores which vary in -shape and size according to the 

 exact composition and concentration of the reacting 

 substances, and he frankly attributes to their varying 

 configuration some of the apparently anomalous 

 instances of "selective" permeability. 



The Ministry of Agriculture has just published in 

 collected form its leaflets dealing with the cultivation 

 and diseases of the potato, the insect pests of fruit 

 trees, and the fungus pests of fruit trees, and these 

 three sectional volumes make a very welcome addition 

 to the literature on diseases of plants in this country. 

 The text of the leaflets has all been rewritten and 

 brought up to date, thus representing the most modern 

 outlook on the subjects considered, and each little 

 volume opens with a ver}- happy introductor\' chapter. 

 In fact, each book is a partial monograph on the 

 specific host plants, and combines in a somewhat 

 rare manner a summary of the latest scientific in- 

 vestigations on the particular diseases and some very- 

 practical measures of prevention and control. The 

 letterpress is good, and the illustrations in many cases 

 noteworthy. These little books are indispensable to 

 practical growers, and should be in the possession of 

 all students of agricultural colleges or agricultural and 

 botanical schools of universities; they really form the 

 nucleus of what might with a little energy be ex- 

 panded into a standard text-book on English plant 

 diseases. A ver\- great deal of credit is due to Messrs. 

 Cotton and Fryer, who have compiled these volumes, 

 and to the Plant Pests and Publications Branches 

 of the Ministry of Agriculture for having had suffi- 

 cient imagination to publish them in so attractive and 

 convenient a form. It only remains to add that the 

 price of two of the volumes is eightpence each, and 

 of the third tenpence, and they are probably the best 

 value in biological literature to be had for the money. 



The law of the geoidal slope and fallacies in 

 dynamic meteorology is the subject of an article in 

 the Monthly Weather Revieiv for October, 1920, by 



