560 



NATURE 



[April 15, 1880 



rays of the solar spectrum are the more active in the 

 process. 



It would be easy to multiply criticisms of this kind, 

 but enough has been already said to show that the book 

 is unsuitable for the use of students, at least of those who 

 are not already tolerably advanced. The first essential 

 of a good handbook for students is that it should give a 

 clear and, as far as possible, complete account of the 

 actual attainments of the science of which it treats. 

 This Prof. Muller's book certainly does not do. Many 

 points of importance are either omitted or treated far 

 too superficially, whereas others of less importance 

 are discussed at great length in a highly theoretical 

 manner, which, be it said, is often ingenious and in- 

 teresting. The book cannot, therefore, be regarded as 

 a successful handbook ; its merits are rather those of a 

 treatise upon those parts of the physiology of plants 

 •which are susceptible of a physical and mathematical 

 treatment. 



It only remains to add that the general appearance of 

 the book, the paper, type, and figures are good, and to 

 express the regret that there is not an alphabetical index 

 at the end which might serve as a guide through the 

 somewhat intricate mazes of the contents. 



OUR BOOK SHELF 



On the Urari, the Deadly Arrow-poison of the Macusis. 



By Richard Schomburgk, Ph.D. 4to. Pp. iS. 



(Adelaide : E. Spiller.) 

 In this pamphlet the author describes the researches 

 made by himself and by his brother, Sir Robert 

 Schomburgk, into the modes of preparation of urari. 

 Although an arrow-poison is prepared by a number of 

 Indian tribes in Guiana, and between the Amazon 

 River and the Orinoco, yet that prepared by the Macusi 

 Indians is much stronger, and other tribes come very long 

 distances in order to obtain it. This greater strength is 

 thought bv the author to depend upon the use by the 

 Macusi Indians of the Strychnos toxifera. The bark of 

 this plant contains all the properties of the urari, and the 

 Macusi Indians add to it a number of other substances. 

 With great difficulty the author prevailed upon an old 

 urari-maker to show him the process of preparing the 

 poison. The ingredients were— bark of Strychnos 

 toxifera, 2 lbs. ; from Yakki (Strychnos schomburgk ii), 

 \ lb. ; Arimaru (Strychnos cogens), J lb. ; Wakarimo, 

 J lb. ; the root of Tarireng, I oz. ; the root of Tararemu, 

 i oz. ; the fleshy root of Muramu (Cissus spec.) ; four 

 small pieces of wood of a tree of the species of 

 Xanthoxyleae, called Manuca. (Manuca is the strong 

 bitter wood of a tree of the Xanthoxyleae. The bark 

 and the root are used as an effective remedy against 

 syphilitic sickness on the Rio Negro, Amazon, and Rio 

 Branco.) 



These ingredients were crushed singly in a mortar, and 

 the bark of Strychnos tox. was thrown first into a pot 

 containing about seven quarts of water. As soon as the 

 water began to boil he added at intervals a handful of the 

 other ingredients except the muramu. The whole was 

 then kept boiling very slowly, the foam being carefully 

 skimmed away, for twenty-four hours, the mixture being 

 kept at an equal heat. At the expiration of that time the 

 extract had been reduced by boiling to about a quart. 

 became thick, and assumed the colour of strong cofiee. 

 It was then strained through a large funnel made of palm- 

 leaves and filled with fresh silk-grass. The filtrate was 

 exposed in a flat vessel to the sun for about three hours, 

 and he then added the slimy juice expressed from the 



muramu root, which had been previously soaked for a 

 short time in the boiling poison. The urari immediately 

 underwent a remarkable alteration, curdling to a jelly-like 

 substance. The poison was then poured into very fiat 

 earthen vessels, in order to still further concentrate it by 

 exposure to the sun. When it reached the consistency of 

 thick treacle it was poured into small calabashes, where it 

 ultimately changed into a hard substance. During the pre- 

 paration a number of superstitious precautions are taken, 

 in order, as they imagine, to prevent the poison losing its 

 efficacy. No certain remedy is known for the effects of 

 the poison ; those employed by the Indians are the juice 

 of sugar-cane either alone or mixed with an infusion of the 

 leaves of the tree Eperua falcata. Salt and urine are 

 sometimes also employed as remedies. 



The author mentions the researches on the physio- 

 logical action of urari by Waterton and Virchow, but 

 seems unaware of, or at least does not allude to, the 

 observations of Bernard, or the more recent works of 

 German observers. This pamphlet is, however, interest- 

 ing as containing the author's own original observations 

 upon the mode of preparation of the urari, made, as they 

 were, under great difficulties. 



Notes of Observations on Injurious Insects. Report, 1879. 



(London : W. Swan Sonnenschein and Allen, 1S80.) 

 This report, for the production of which we are mainly 

 indebted to the exertions of Miss E. A. Ormerod, the 

 Rev. T. A. Preston, and Mr. E. A. Fitch, is, this year, 

 one of unusual interest, inasmuch as it reviews the de- 

 structive work of the insect world to our garden and field 

 crops during a summer unequalled for its want of sun- 

 shine and continued heavy rains. Moreover, owing to 

 the energy displayed by the editor in inducing gardeners, 

 foresters, &c, to record what observations they may have 

 made, we have, as the result, a very full and very varied 

 report. Notwithstanding that the temperature was below 

 and the rainfall above the average, "the returns show 

 insect attack fully up to the usual amount, and insect 

 presence often exceeding it. The unusual cold of the 

 winter and the depth to which the frost penetrated the 

 ground do not appear to have acted prejudicially on larvae 

 subjected to them, either at the time or in subsequent 

 development, and the only cases in which the weather 

 appears notably to have had effect in ridding us of insect 

 attack is where the persistent rainfall or the tremendous 

 downpour of summer storms have fairly swept the insects 

 from the plants, or in some cases of leaf-feeders, where 

 the plant-growth has (conjecturally) been driven on past 

 the power of the larvae." 



Referring to the power of the frost " during the past 

 winter" (the report is dated December 19 last), it is 

 stated that at Dalkeith it penetrated the earth to a depth 

 of fifteen inches, while in Perthshire it went down to 

 from twenty to twenty-four inches. Miss Ormerod 

 alludes to the prevalent idea that " cold kills the grubs,'' 

 and gives her experience of an examination of all larvae 

 and pupae found fully exposed to its influence, whether 

 unsheltered, under bark, or in frozen ground. In every 

 case, even where the ground was frozen so hard that it 

 required a hammer to break it, and the larvae and pupae 

 were perfectly rigid, on thawing they showed no sign of 

 injury, " and in the case of the larvae of the cabbage 

 weevil (which was the only instance in which any imme- 

 diate action. was to be expected) they continued the 

 operation of making their earth cases for pupation (as is 

 usual with this grub on disturbance from the gall) as if 

 nothing had happened." 



The extreme severity of the winter was also favour- 

 able, in other respects, to insect-preservation, large num- 

 bers being secured from the attacks of birds by being 

 buried under the snow or in the frost-bound ground. 



The report, which embodies notes from observers all over 

 the United Kingdom, is one of very great value not only 



