2 SO 



NA TURE 



[January a, igob 



Laramie Cretaceous, namely, Tyrannosaurus rex and 

 Dynamosaurus imperiosus The former appears to have 

 been unprovided with armour, and is estimated to have 

 measured 39 feet in length ; ii walked on the hind-limbs 

 only, with the top of the skull raised about 19 feel from 

 the ground. On the other hand, Dynamosaurus was an 



armoured type with al I a dozen lower teeth, and a 



number of curious prominences on the inner margin of the 

 jaw. In this comparatively small number of teeth ii seems 

 to differ from Leidy's Dinodon, in which some of the 

 teeth were serrated. A third type, Albertosaurus sarco 

 phagus, is based on a skull from Albert province, Canada. 

 It is apparently more specialised than Dine, don in the 

 reduction of the truncated anterior teeth, and more 

 primitive than Dynamosaurus in tin- possession of a larger 

 number of teeth, which are of a less specialised type. 



We have received four numbers (inclusive of one devoted 

 to the record of last year's meetings) of the fourteenth 

 volume of the Transactions of the Academy of St. Louis. 

 In the bulkiest of these, comprising no less than 24S pages, 

 Mr. T. I.. Casey revises the American representatives of 

 that section of the staphylinid or short-elytraed beetles 

 km wn as the Pcederini, the memoir being, of course, 

 interesting only to specialists. In a second paper Mr. S. 

 Weller describes, under the name of Paraphorhynchus, a 

 new genus of rhynchonella-Iike brachiopods from the 

 Kinderhook formation of the Mississippi. In a third papi r 



the fresh-water molluscan fauna of McGregor, Iowa, I is 



the subject. Mr. F. C. Baker communicates 50 interest- 

 ing information with regard to the pearl-fisher) of that 

 district. The unios .are fished up by means of a dredge 

 armed with four-pronged " crowfoot " hooks, and it is 

 believed that malformed specimens are more likel) to 

 tain pearls than those with normal shells. These 

 "■rippled" mussel-, or "clams," are believed bv the 

 writer to owe their injuries to the action of the dredge 



it-elf. 



The last published number ol Biometrika contains an 

 important paper by Mr. A. O. Powys on fertility, duration 

 of life and reproductive selection in man, with their 

 mutual relations. Several of his results, which are derived 

 from the statistical data of New South Wales, are of high 

 interest. He finds that women with families ol five or -i\ 

 children have .1 licit,., expectation of life after forty-five 

 than mothers of either a larger or smaller number of 

 offspring. The married have a similar advantage over the 

 single. Vnother conclusion drawn by Mr. Powys from his 

 figures is that " up to the pros,. n( there is but little 

 Malthusian restraint upon the population in New South 

 Wales- what little there may I"- apparently being con- 

 fined to the professional, domestii end tmercial classes." 



He confirms Prof. Karl Pearson's view that society 1 a.1 

 presenl being recruited from below— mainly from the 

 artisan class. A useful craniological contribution to the 

 stud) ol inter-racial correlation in man is furnished by 

 E. Tschepourkowsky, of Moscow, and Mr. E. II. J. 

 Schuster publishes the first instalment of a catalogui of 

 the fine collection of skulls in the Oxford Museum, on the 

 basis of a manuscript catalogue prepared some yi 

 b) Dr. Hatchett Jackson. Dr. Brow nice puts the la. is 

 of the immunit) against small-pox conferred b) vaccin- 

 ation and re-vaccination on a firm statistical basis, and 

 Mr. John Blakeman upplii probable error tests 

 significanci 01 otherwise ol the difference between correla- 

 tion ratio and coefficient, and consequently ol the exi tence 

 or non-i 1 a given population of true linear n- 



ii 'i Mr. 1. alter deals with the measurements of 

 NO. 1888, VOL. 72>] 



1572 specimens of cuckoos' eggs. These, he considers, 

 tend to confirm Prof. Newton's suggestion that there are 

 certain subraces of cuckoos which " in the main confine 

 their attentions, generation after generation, each to its 

 own particular variety of foster-parent." In the "Miscel- 

 lanea," Mr. W. Palin Elderton proposes new methods for 

 the calculation and adjustment of moments. 



Mr. J. II. Hart, the superintendent of the Royal 

 Botanii Gardens, Trinidad, records the discovery of a 

 water-plant, probabl) a species of Nitella, in the Pitch 

 Lake La Brea, which produces peculiar pear-shaped organs 

 on the stems. These are hollow, and have large openings 

 into the interior, fringed with simple or branched hairs, 

 and within some of them mosquito larva' were observed, 



ap] ally caught and killed by the plant. The suggestion, 



therefore, is made that the plant might be useful for 

 mosquito destruction. 



The use of copper sulphate in the purification of water 

 supplies has from time to time been referred to in these 

 C< lumns. Dr. Howard Jones, the medical officer of health 

 for Newport, Mon., reports the successful employment of 

 the method at Newport. Copper sulphate, to the extent of 

 1 Hi. per million gallons, proved efficient in removing an 

 objectionable fishy odour and rendering the water of the 

 reservoirs bright and clear {Water, December [5, 5), 



Ai a meeting ol the Royal Statistical Society on 

 December 19, 1905, Drs. Newsholme and Stevenson read 

 an important paper on the decline of human fertility in 

 the United Kingdom and other countries a, shown by 

 corrected birth-rates The) pointed out that corrected 

 birth-rates measure the tendency of communities to increase 

 In natural mean-, u-. by the excess of births over deaths, 

 or, in other words, their fertility, just as corrected death- 

 rale- measure the tendenc) to decrease. The ordinary 

 "crude" birth-rate is deceptive, since it fails to make 

 allowance for the fact that some populations include a 

 much larger proportion than others of wives at reproductive 

 ages, and lor ibe further fact that the potential fertility 

 of women steadil) decreases during the reproductive period 

 until its end is reached. The necessity for correction was 

 illustrated by numerous examples. Thus the crude birth- 

 rate of Ireland in 1903, 23-1, is little higher than thai of 

 France in 0102, which was 21-7; but the French birth-rate 

 is practically unaltered by correction, whereas that of 

 Ireland is increased to no less than 36-1. This remarkable 

 result is due to the fact that, although both countries have 

 approximately the same proportion of women aged fifteen 

 to forty-five in their populations, 52-5 per cent, of these in 

 France are married a- againsl 32-5 per cent, in Ireland. 

 Of the countries studied, Ireland .done- -how- an increase 

 of fertility (; per cent.) during the last twenty-two year-. 

 Ilie conclusion arrived to is that the decline in the birth- 

 rate is associated with a general raising of the standard 

 ol comfort, and is an expression of the determination of 

 the people to secure this greater comfort; and the authors 

 anticipate a- a result a deterioration of the moral, if not 

 also of the physical, nature of mankind. 



Ciel ei Terre for November 15, 1905, contains a useful 

 summary of an elaborate discussion by M. A. Angol on 

 the temperature of France and adjoining countries. The 

 original paper appeared in a recent number of Annates de 

 Geographic : it deals chiefly with the temperature of 



I 1 to which the following remarks entirely re 1 Vs 



regards the annual means, the isotherms in the north ol 

 the countr) show a decided inclination from north-west 

 to south-easl . this i- due to the- fact that, generall) speak- 



