August ii, 1910] 



NATURE 



181 



descriptive anatomy, as in the case of the elaborate memoir 

 bv Albert Bauer on the musculature of the water-beetle, 

 Uytiscus marginalis, to the most minute investigations 

 in cvtology and protozoology. Heinrich Stauffacher's 

 ■■ Beitrage zur Kenntniss der Kernstrukturen " affords a 

 beautiful example of the results to be obtained by modern 

 cvtological methods. Its chief interest, perhaps, lies in 

 the demonstration of " nuclear bridges " (Kernbriicken) in 

 the form of threads which connect the protoplasm of the 

 nucleus with that of the cell body. W. Knoll, in the next 

 memoir, deals critically with the question of the existence 

 of such connections between karyoplasm and cytoplasm, 

 and demonstrates their existence in the leucocytes of the 

 human body. .Amongst the other papers we have only 

 space to mention the first part of C. Janicki's studies on 

 parasitic flagellates, dealing with two species of Lopho- 

 monas found in the cockroach. The application of modern 

 technique to the investig.ttion of the Protozoa, as we hardly 

 need point out, marks the commencement of a new era 

 in the study of these organisms, revealing complexities of 

 structure previously unsuspected, as the plates illustrating 

 the remarkable genus dealt with by Janicki abundantly 

 tpslify. 



Is- the Bio-chemical Journal for June (vol. v., No. 4) 

 Prof. Benjamin Moore and Dr. Stenhouse Williams detail 

 experiments on the effect of an increased percentage of 

 o.xygen on the vitality and growth of bacteria. Of twenty- 

 six organisms tested, two may be termed oxyphobic. 

 These are the tubercle bacillus, which is not only arrested 

 in growth, but is actually killed by a high percentage of 

 oxygen, and the plague bacillus, which, though not killed, 

 uniformly refused to grow in percentages of o.Kygen from 

 60 to 91. The staphylococcic group was also adversely 

 affected, but the remainder, including the typhoid, 

 dysentery, glanders, diphtheria, anthrax, and cholera 

 organisms, was unaffected. 



Ix the Bulletin of the Johns Hopkins Hospital for July 

 (xxi., No. 232) Dr. John L. Todd contributes an excellent 

 review of the recent advances in our knowledge of tropical 

 diseases. He summarises the most striking additions to 

 our knowledge of tropical medicine during 1909 as being 

 li) the discovery of infantile kala-azar in northern .Africa; 

 (2) the discovery of a new human trypanosome in South 

 America ; (3) the researches which have made it almost 

 certain that the parasite of sleeping sickness undergoes a 

 developmental cycle in the tsetse-fly which conveys it ; and 

 (4) the transmission of typhus fever to monkeys by the 

 bites of body lice. 



Important information with regard to the thyroid body 

 and related structures is supplied in a paper by Mr. F. D. 

 Thompson, just published in the Phil. Trans. A thyroid, 

 thymus, and post-branchial body are developed in the gill- 

 slits of elasmobianch fishes; but parathyroid and carotid 

 glandules have not been observed. In teleostomous fishes. 

 on the other hand, the only organs of this nature are the 

 thyroid and thymus ; bat parathyroids make their appear- 

 ance in amphibians and reptiles, in the former of which 

 the post-branchial body is retained. In these groups the 

 structure of the various glands of the thyroid type differs 

 considerably ; but in mammals such structural differences 

 tend to disappear, and in certain circumstances the para- 

 thyroids may develop colloid vesicles, and thus become prac- 

 tically identical with the thyroid. The thyroid and para- 

 thyroids may accordingly be regarded as structures of 

 diverse embryological origin, which remain distinct in lower 

 vertebrates, but in mammals become intimately related and 

 constitute a single apparatus. 



NO. 2128, VOL. 84] 



So closely are fungi and bacteria often associated in 

 their destructive action on plant tissues, that it is extremely 

 difficult to determine which organism is taking the lead. 

 Some botanists, including De Bary, Hartig, and 

 A. Fischer, have expressed themselves very sceptical as to 

 the possibility of bacteria penetrating living plant tissues ; 

 others, notably E. F. Smith in the United States and 

 Prof. M. C. Potter, have offered results of experiments as 

 proof that bacteria do pass into the living plant and pene- 

 trate through cell walls. The subject is fairly discussed 

 by Prof. Potter in his presidential address delivered before 

 the British Mycological Society, and published in their 

 Transactions. In addition to other arguments, the author 

 refers to his experiments upon the white rot of turnips, 

 when the bacterium Pseudomonas destructans was not 

 only isolated and re-inoculated on the host, but it was 

 demonstrated that oxalic acid was produced by the 

 bacterium, which acts as a toxin in plasmolysing and 

 l^illing the protoplasm ; he also states that subsequently 

 penetration of the cell wall by bacteria was observed. 



We have received from Mr. E. Reinders a copy of his 

 paper on the "Sap-raising Forces in Living Wood," 

 read before the Royal Academy of Sciences of .Amsterdam, 

 January 29. After a short discussion of the avail- 

 able evidence on the problem of the ascent of water 

 in trees, he gives an account of his own experiments. His 

 results are of interest, as supporting the view that water 

 is raised by a pumping action of the living elements 

 of the wood (a theory generally connected with the name 

 of Godlewski), and the detailed description of Mr. 

 Reinders 's work will be expected with interest. Mr. 

 Reinders proceeds from the fact " that manometers 

 placed at different heights up the trunk behave quite in- 

 dependently of one another. Sometimes one shows a lower 

 pressure, sometimes the other." This irregularity is 

 assumed by Reinders to be due to the pumping action of 

 the living elements in the wood, and he proceeds to test 

 his view by killing the stem either by steam or by an 

 induction shock. He found that " as soon as the trunk 

 w'as dead the difference of pressure followed the same 

 rule as would be e.xpected to apply to a glass tube." In 

 one striking case the stem was not killed, but so seriously 

 injured that five days elapsed before the behaviour of the 

 manometers became once more " as irregular as in living 

 trees.". It should be added that Mr. Reinders assumes that 

 in dead trunks which can no longer act as pumps, water 

 ascends " through other causes, e.g. with the help of 

 cohesion." 



In the June number of the Agricultural Journal of the 

 Cape of Good Hope is an article on the dried fruit and 

 raisin industry recently established in Cape Colony. 

 .Although no great amount of produce has yet been raised 

 it appears that the local conditions are suitable for success, 

 and when certain improvements are effected there is the 

 prospect of supplying the needs of the colony and even 

 P'?rhaps of establishing an export trade. 



We have received from the University of Wisconsin 

 .Agricultural Experiment Station several " Research Bulle- 

 tins " devoted to subjects of scientific interest. A study 

 was made of the physiological effect on the cow of the 

 milking machine which is now threatening to supplant the 

 cowman and the milkmaid. No bad effects on the general 

 health of the animal or the state of the udder could be 

 found, and for an ordinary dairy herd the machine worked 

 very well. Whether it would give equal results in a high- 

 class herd is not certain ; but here the economic problem is 



