262 



NATURE 



[April 28, 1910 



Australasia, and the United States, still less why 

 the whole of the coals of Great Britain should be con- 

 sidered to be adequately represented by analyses of some 

 half a dozen Welsh coals. Such a comparative list should 

 either be truly representative or else (and perhaps better) 

 be omitted altogether. There appears to be no obvious 

 reason why Mr, Dowling should want any new-fangled 

 mode of classification in order to enable him satisfactorily 

 to classify these coals. P"or most practical purposes the old 

 classification of Gruncr answers perfectly well, and if anj-- 

 thing more precise is required, the fuel ratio (or the ratio of 

 the fixed carbon to the volatile combustible matter) suffices 

 for most purposes. The ratio suggested by the author, 

 which he calls the " split volatile " ratio, appears to serve 

 no particular purpose, and, on the other hand, would enable 

 a coal to be put into almost any class at will by merely 

 drying it more or less thoroughly before analysing it. 



The two remaining treatises deal in more or less detail 

 with ore deposits in definite regions, differing mainly in 

 this respect that the copper deposits of the Whitehorse 

 Belt have been opened up pretty extensively and are being 

 actively worked to-day, whilst the iron ores of the Ottawa 

 and Gatineau Rivers are not to-day of any economic 

 importance. 



The last treatise on the list is in some respects the least 

 satisfactory. So long as the writer keeps to his proper 

 subject, namely, a description of the ore deposits, their 

 modes of occurrence, distribution and geology, there is 

 little fault to be found, although the language is in places 

 somewhat less clear than might be wished. It is, how- 

 ever, when the author ventures into metallurgical dis- 

 cussion that he seems to go widely astray. It is incom- 

 prehensible how anvone could write such a sentence as 

 the following in discussing the metallurgv of iron (p. 

 104) : — " By no known chemical or electro-thermic process 

 can phosphorus be eliminated from the bath of any of the 

 diverse metallurgical furnaces." The author seems to be 

 exceedingly sanguine as to the future of the electrical pro- 

 duction of pig-iron in the Dominion, an opinion which he 

 seems to share with some other Canadian geologists. It is 

 soniewhat curious to note that it is the geologists who are 

 urging on this metallurgical development, whilst manu- 

 facturers of iron appear to be more than doubtful as to its 

 economic possibilities. Whether this is due to the well- 

 recognised conservatism of the latter and the advanced 

 scientific enterprise of the former, or whether it is a case of 

 geologists rushing in where iron-masters fear to tread, is 

 not for us to determine. Henry Louis. 



RECENT PAPERS ON BIRDS. 

 jV/TR. C. W. BEEBE is to be congratulated on his 



attempt _(Zoo2o^tca, No. 5) to explain the "racket- 

 making " habit of the motmots. These birds, it is almost 

 unnecessary to mention, are in the habit of removing the 

 vanes of the middle pair of elongated tail-feathers for a 

 certain distance, so as to give them a racket-like form 

 very similar to that which occurs naturally in certain king- 

 fishers and humming-birds. It is shown that the length of 

 feather thus devaned is invariably constant, even when the 

 adjacent pair of feathers, which might serve as a guide, 

 has been removed. Further, the portion destined to be 

 stripped has the vanes markedly narrower than in the rest 

 of the feather, while the component barbs and barbules 

 are much weaker and less coherent than elsewhere, so 

 that their removal is a comparatively easy matter. Con- 

 sequently, in the course of the preening to which these 

 birds subject all their tail-feathers, the weak area in the 

 vanes of the middle pair becomes stripped, with the pro- 

 duction of the symmetrical pair of terminal rackets. The 

 original cause of the narrowing and degeneration in the 

 affected area is still unknown, but the author is of opinion 

 that it is not a case of the inheritance of an acquired 

 character. 



In No. 2 of the same serial Mr. Beebe gives the results 

 of his observations on the habits of that remarkable bird 

 the_ hoazin, or hoatzin (Opisthocomus cristatus), made 

 during a visit in March, 1908, to Venezuela, and a second 

 in April of the following year to British Guiana. As young 

 birds were not to be found, the notes relate only to the 

 adult. Mr. Beebe commences his account by mentioning 



NO. 2 113, VOL. 83] 



that the crop of the hoazin is unique on account of having 

 assumed the structure and function of the gizzard of 

 other birds, being much larger than ordinary, with the 

 walls thick and muscular instead of thin and flabby. 

 Despite this specialised feature, the primitive character of 

 this bird is indicated by many points, the vestigial claw 

 of the third digit of the wing linking it with Archa;o- 

 pteryx, while another claim to primitiveness is apparent 

 in the quadrupedal habits of the young. Thickly wooded 

 river-valleys form the haunts of the hoazin, of which Lower 

 Amazonia may be considered the centre, the distributional 

 area, according to our present information, being in several 

 instances discontinuous. The bird has a peculiarly dis- 

 agreeable odour of its own, which is, however, in Mr. 

 Beebe's opinion, less powerful than commonly reputed, and, 

 at all events, insufficient to render it immune to the attacks 

 of parasites. In general character the nest and eggs are 

 very similar to those of the Guiana green herons 

 (Butorides), but are placed higher above the water. Both 

 sexes assist in nest-building, and two eggs seem to be 

 the usual number in a clutch. There is no foundation for 

 the assertion that these birds are polygamous, or, of 

 course, for the old legend as to their snake-eating habits. 



The institution and celebration of the first " bird-day " 

 in the Australian Commonwealth is recorded in the 

 January number of the Emu. October 29, 1909, was the 

 date selected in Victoria, when the celebration proved a 

 thorough success, parents, teachers, and scholars joining 

 in with enthusiasm, and visits being paid to noted bird- 

 haunts in the different districts. Numerous nests were 

 examined, but in no instance were either birds or eggs 

 molested. A certain amount of preliminary work had to 

 be done in teaching the children the names of many of 

 the local birds, for which purpose special lists were pre- 

 pared. In the same issue Mr. C. Barrett describes the 

 nesting of the rock-parrakeet (Neophema petrophila) on 

 Goat Island, Kellidic Bay. Here this appropriately named 

 species rears its young in hundreds, the eggs being often 

 laid deep down in burrows, although higher up on the 

 cliffs they are frequently placed on the bare rock, in most 

 cases under the protection of a raised stone. 



In the March number of the Zoologist Mr. J. M. Dewar 

 describes the manner in which the oyster-catcher breaks 

 the shell of the purple whelk {Purpura lapillus) in order 

 to be able to feed on its contents. As the soft-parts of 

 this mollusc are much more difficult of access than those 

 of mussels and limpets, the bird only occasionally attacks 

 the whelk, and perhaps never does so at all in some locali- 

 ties. When a mollusc is to be operated upon, it is carried 

 to some convenient spot, often a crack or hollow in the 

 rock, or it may be a hard patch of sand, where it is laid 

 with the mouth uppermost. The upper half of the beak 

 is then introduced into the aperture, and an attempt made 

 to punch out a small fragment from the opposite surface 

 of the shell. If this is successfully accomplished, and the 

 piece punched out is of small size, the beak is introduced 

 into the new aperture, and the same process repeated 

 higher up the shell, when, if it succeeds, the soft-parts can 

 be scooped out. In cases where the first hole is larger, 

 the latter operation can be accomplished by that aperture. 

 Frequently the shell defies the bird's efforts. 



The January number of the Victorian Naturalist con- 

 tains the report of a paper, by Mr. A. H. E. Mattingley, 

 on the breeding-habits of Australian cuckoos, in which it 

 is stated that only an infinitesimal proportion of their eggs 

 approximate in size, colour, markings, and shape to those 

 among which they are laid. There are, moreover, 

 numerous instances in which Australian cuckoos have laid 

 in the nests of graminivorous birds, with the consequent 

 starvation of the young. In other instances cuckoos lay 

 in nests already containing eggs of their own species, while 

 they also make use of nests too small to contain the 

 voung bird in comfort. It is concluded that, so far at 

 least as Australian species are concerned, cuckoos, in place 

 of possessing an instinct leading to the selection of suit- 

 able foster-parents, lay their eggs haphazard. 



Ever since the year 1904 Dr. F. .\. Forel has been 

 endeavouring to ascertain the approximate number of 

 individuals of the black-headed gull (Larus ridibundus) 

 which resort to Lake Leman during certain months of 

 the year, arid likewise to explain the reason why many. 



