374 



NATURE 



[September 8, 1923 



of Monodontus ttigonocephalus of sheep, and a descrip- 

 tion by Dr. R. J. Ortlepp of the hfe-history of 

 Syngamus trachealis, the gape-worm of chickens. The 

 eggs in the uterus of the female Syngamus do not 

 develop there beyond the i6-cell stage, and they are 

 usually laid in this or in the 8-cell stage, and when 

 kept in well aerated water at 25° C. they take about a 

 week to develop into infective larvae, undergoing one 

 moult during this period. The second stage or 

 infective larvae are sheathed ; they are non-climbers, 

 do not penetrate the skin, and cannot resist desiccation. 

 Larvae swallowed by chicks reach the lungs in about 

 24 hours. The path of migration from the digestive 

 tract has not been traced but the author inclines to 

 the view that the larvae are carried like those of Ascaris 

 and Ancylostoma, i.e. in the blood-stream through 

 the heart to the lungs. In the lungs the larvae grow 

 considerably and undergo two further moults, the 

 final or fourth stage being reached in about five days 

 after infection. The young worms then pair and 

 migrate into the trachea, where, 10 to 14 days later, 

 they attain sexual maturity. Thus the whole life- 

 cycle is completed within a month. Dr. Ortlepp 

 supports the view of Walker and Waite that, in Nature, 

 chickens contract the infection by eating earthworms 

 infected with the larvae. 



A Physiological Function of the Pituitary 

 Gland. — The chemical constitution of the active 

 substances extracted from the posterior lobe of the 

 pituitary gland is still unknown, but their important 

 pharmacological properties have received much 

 attention and are accurately determined. Until 

 recently, however, the physiological functions of the 

 organ remained a matter for speculation. In a 

 series of researches on pigmentary changes, L. T. 

 Hogben and F. R. Winton have now succeeded in 

 defining such an essential endocrine function in 

 amphibia. They showed (Proc. Roy. Soc, 1922, 

 B, vol. 93, 318-329) that injection of traces of posterior 

 lobe extracts into pale frogs (melanophores contracted) 

 induces profound darkening of the skin (expansion of 

 the melanophores). This action is not elicited by 

 other tissue extracts, whereas the minute posterior 

 lobe of a single frog includes enough active substance 

 to darken at least fifty other pale individuals. So 

 sensitive is the reaction that it may serve as a method 

 of detection or of rough estimation of the potency of 

 such extracts (Biochem. Journ., 1922, vol. 16, 619-630). 

 This response is a direct action on the skin, as can 

 be demonstrated by experiments on the isolated 

 skin, and by the inefficacy of drugs with paralytic 

 action to prevent it. Stimulation of nerve trunks 

 and the administration of the drugs showed no direct 

 evidence of nervous mechanism for pigment control 

 (Proc. Roy. Soc, 1922, B, vol. 94, 151-162). After 

 extirpation of the whole of the pituitary gland the 

 skin always became quite pale and the melanophores 

 completely contracted. This pallor persisted per- 

 manently even in the presence of the optimum 

 conditions (cold, wet, and shade) for darkening of 

 normal animals. Injection of posterior lobe extracts 

 was followed by profound darkening with complete 

 melanophore expansion, which lasted for a varying 

 time according to dosage and other conditions, the 

 animals then returning to permanent pallor. Frogs 

 from which anterior lobes only were removed, or with 

 the brains exposed, were indistinguishable from 

 normal animals with respect to their pigmentary 

 reactions. The failure of colour response associated 

 with complete hypophysectomy is therefore due to 

 absence of posterior lobe secretion, and not attribut- 

 able to anterior lobe deficiency or to the operative 

 technique employed (Proc. Roy. Soc, 1923, B, vol. 95, 

 15-30)- 



NO. 2810, VOL. 112] 



Thi: Ethyl Alcohol Industry. — The Chemic i 

 Trade Journal for August 3 prints a review of t! 

 ethyl alcohol industry. The pioneer of synv 

 alcohol was Hennell, who, in 1828, found that di 

 and distillation of a sulphuric acid solution > • 

 yielded alcohol ; this reaction also has c< 

 theoretical significance. During the V\ar, 

 alcohol was made from acetylene, which in its 

 was produced from synthetic calcium -• ■ 

 acetylene was hydrated directly to a< 

 the presence of a mercury salt), wii....> 

 reduced to alcohol by the Sabatier and ^^ 

 reaction. Under present economic condii;,,., wt ; 

 many appears to make most of her alcohol b. 

 fermentation methods. The article includes a snrv. 

 of the physical properties of alcohol, its indu 

 applications and future prospects for the svrn 

 product. 



Celtium or Hafnium ? — Chemistry and Industr 

 for August 10 contains an important article by Prol. 

 G. Urbain under the title " Should the Element of 

 the Atomic Number 72 be called Celtium or Hafnium?" 

 Prof. Urbain claims that he has had this element 

 in his possession and under his observation since 191 1, 

 when he suggested the name celtium for it ; that 

 although iMoseley in July 1914 (when Urbain visited 

 him in Oxford) was not able to detect the characteristic 

 lines of No. 72 in the fraction submitted for test, 

 two of these lines were, in fact, detected by Dauvillier 

 in 1922, in the spectrum of the same material, bv 

 making use of improved experimental methods ; that 

 if any doubt existed as to the identity of these lines, 

 it -was finally removed by a direct comparison (by 

 the method of coincidences) of lines from the 1911 

 fraction with a newly-prepared fraction from a 

 zirconium mineral, in which the presence of No. 72 

 is not now questioned, in view of the six characteristir 

 lines recorded by Coster and Hevesy. Under th-! 

 conditions the claim of the later workers to luiM; 

 discovered a new element (since it could scarcely 

 be based on a more accurate measurement of the 

 same physical property) appears to depend on the 

 assumption that a " fourth group " element could not 

 have been present in the rare earth fractions examined 

 twelve years previously by Urbain. Prof. Urbain 

 claims that it was actually there, and that there is 

 no theoretical objection to its presence, since " there 

 is no law which compels the elements to associate 

 themselves strictly in accordance with their classifica- 

 tion." Moreover, he had already, in 1921, himself 

 agreed to Perrin's classification of celtium as a 

 fourth-group element, in spite of the fact that he had 

 found it in a rare-earth mixture. He p)oints out 

 that there are many elements with different valencies 

 which cling together so closely that one cannot 

 separate them except by very laborious treatment, 

 and in particular that thorium, which is quadrivalent, 

 is in fact always accompanied by the tervalent rare 

 earths. Again, Bohr's theory only applies to free 

 atoms and simple ions, and affords at present no 

 guidance whatever as to the behaviour of complex 

 ions ; it is therefore not able to predict the chemical 

 properties of elements which form double-salts in 

 solution. These give rise, however, to many sur- 

 prising cases of complete isomorphism, e.g. the 

 fluorides of quadrivalent titanium with the oxy- 

 fluorides of quinquevalent niobium. Prof. Urbain 

 claims that " no purely theoretical reasoning ought 

 to prevail against a well-established question of 

 fact," and that as regards the presence of celtium 

 in his rare-earth fractions, the facts are not only 

 well established but also in strict accord with general 

 chemical experience. 



