174 



A'A TURE 



[August 5, 1909 



forms of government which give to the working class in 

 the community an effective voice in policy and administra- 

 tion." 



" The temper, the outlook, the recreations, and the 

 ideals of a nation may be so refined and raised by the 

 right kind of training as to secure for the mass of the 

 people a more choice worthy life." J. Wilson. 



CHANGES IN COLOUR AMONG TROPICAL 

 FISHES. 



'T'HE Zoological Society of New York recently issued a 

 very interesting paper written by Mr. C. H. Townsend 

 on the instantaneous changes of colour among tropical 

 fishes (thirteenth annual report, 1909). The specimens 

 came from the Bermudas, and are kept under favourable 



Rindeil I'liase. 

 Two Colour-phasss of the Nassau Grouper i^E/>inc/>hclus striatn. 



conditions in the aquarium of the society. The changes of I 

 coloration " begin to be in evidence within an hour of the I 

 arrival of new specimens, or as soon as they recover from 1 

 the alarm produced by handling, and arc produced as long 

 as the fishes live in the tanks, which, in some cases, may 

 be several years." 



The phases of coloration are illustrated by a striking 

 series of photographs, two of which are reproduced. From 

 these it wnll be seen that the fish can pass from a uniformlv 

 dark (plumbeous) colour to a banded phase with white 

 markings. Four other phases can also be assumed, includ- 

 ing a uniformly creamy-white one. This plasticity of 

 coloration is characteristic of most of the fish dealt with, 

 which include Serranidne, Scarid.ie, Teuthidida?, and Scor- 

 paenid^. There is frequently a pale and a dark monochrome 



NO. 2075, VOL. Si] 



phase when the fish is at rest. Under any excitement, such 

 as the presence of visitors, the fish assumes a parti-coloured 

 aspect. This pa^jer clearly shows how inadequate and 

 misleading are many of the descriptions of colour hitherto 

 accepted, and is a very suggestive and attractive piece of 

 work, .^n error occurs on p. 3, where it is said that " their 

 different colours result from muscular action upon one or 

 more kinds of cells." The mechanism of colour-change is 

 not muscular, but nervous. 



MINERAL OUTPUT OF THE UNITED STATES.i 



T^HE well-known publication referred to below now 

 appears in a form slightly diliferent from the one to 

 which we have hitherto been accustomed, being issued in 

 two volumes, the first devoted to the Metallic products 

 and the second to the Non-metallic 

 products ; this is done in consequence 

 of a recent legislative enactment (.\ct 

 of May 27, iqoS), and presents some 

 .idvantages, though it might be well to. 

 submit, with all respect, to the Govern- 

 ment of the United States, that these 

 i.md sundry other) publications of th^ 

 I nited States Geological Survey stand 

 n far greater need of condensation 

 than they do of expansion. When a 

 work becomes unwieldy, there are two 

 Dbvious remedies, either to issue it in 

 iwo volumes or to compress the in- 

 formation it conveys into smaller com- 

 |iass ; the latter is no doubt the more 

 iliflicult proceeding, though the one 

 I hat best serves the interests of the 

 readers, and it is a matter of regret 

 that, in this case, the line of least 

 resistance has been followed. In the 

 present instance it leads also to a few 

 anomalies, as, for instance, the in- 

 clusion of crushed steel (as an abrasive) 

 and of certain other metalliferous 

 materials, yuch as arsenic, man- 

 ganese, chromite, &c., in the voluine 

 devoted to non-metallic products. 



It is greatly to be regretted that 

 the mineral statistics of the United 

 States are issued in a form that makes 

 comparisons with the mineral output 

 of other nations difficult ; for ex- 

 ample, the various values of the metals 

 are reported, not in the form of ore, 

 but in the metallic state, though 

 obviously the value in this form 

 includes the cost of reduction of the 

 metal, and leads to very serious dupli- 

 cation, W'hich the compilers appear to 

 have overlooked, although the intro- 

 duction lays stress on the statement 

 that " all unnecessary duplication has 

 been excluded." To take an example, 

 the production of iron ore is not given, 

 but instead of it that of the pig-iron 

 smelted from it, namely, nearly 26 

 million tons, valued at about 530 

 million dollars. Now the production 

 of coke for the same year was 40 

 million tons, produced from 62 million tons of coal, 

 valued at nearly 73 million dollars. Practically the whole 

 of the pig-iron produced was made with coke as fuel, 

 and, in the absence of exact figures, it will probably 

 be a near approximation to the truth if we assume 

 that three-fourths of the coke production, or, say, 

 30 million tons, was consumed in the production of the 

 above pig-iron, so that coal to the value of, say, .S5 million 

 dollars was utilised in this way, and this suin is accord- 

 ingly included in the above valuation of the pig-iron pro- 

 duction ; it is, however, also included in the sum total of 

 the value of the coal production, and thus enters twice 



1 Mineral Resources of the United .S-at^s, Calendar Year 1907. Part I., 

 Metallic Produrts. Pp. 747. Part II.. Non-ni-tatlic Products. Pp. 897. 

 (Washington : Government Printing Office, 190S.) 



