Apkil 19, 1895.] 



SCIENCE. 



445 



would stand to uitrogeii in the siime relation 

 as ozone to oxygen. There is, however, the 

 fundamental difl'erence that argon and ni- 

 trogen are not transformable into one an- 

 other, any more than the isomeric or poly- 

 meric metals. "Without insisting upon 

 points which are still conjectural, M. Ber- 

 tlielot observes that in any case he has de- 

 monstrated that the inactivity of argon dis- 

 appears in the conditions he describes. 

 "When the gas can be obtained in consider- 

 able quantities, he says it will be easy by 

 ordinary chemical methods to take these 

 primaiy combinations, or their analogues 

 obtainable with oxygen, hydrogen, or water, 

 as a point of departure for the preparation 

 of the normal series of more simple com- 

 pounds. — London Times. 



At the anniversary meeting of the Chem- 

 ical Society, Professor Eamsay stated that 

 he had examined the gas (which according 

 to an observation of Hillebrand's was nitro- 

 gen) given ofl' bj' the mineral clevite when 

 treated with sulphuric acid, and discovered 

 that it contained argon. Spectroscopic ex- 

 amination showed a very bright yellow line 

 nearly coincident with the yellow sodium 

 line. This line was found to be identical in 

 position with the j'ellow line observed in 

 the spectrum of the sun's chromosphere, 

 and attributed to the hypothetical element 

 helium. AVhether helium could be sepa- 

 rated from argon remained to be seen. Mr. 

 Crookes gave some additional particulars of 

 the spectrum of the gas from clevite. He 

 found certain coincidences with the band 

 spectrum of nitrogen, particularlj' in the 

 ultra violet region, but some lines were 

 present which were not found in the nitro- 

 gen spectrum, and vice versa. 



Dr. B. Br.\uner, Professor of Chemistrj- 

 in the Bohemian Universitj-, Prague, has 

 written to Xature, suggesting that argon 

 possibly exists in nebuhe. He points out 

 that a strong argon line, measui*ed by Mr. 

 Crookes, has practically the same wave- 



length as the chief nebula line, and thinks 

 that the line at /. .3729.8 in the ' blue' spec- 

 trum, of the new sub.stauce represents tlie 

 line at I 3730, found in the spectra of nebuhe 

 and white stars. 



PALEONTOLOGY. 



Professor H. J. Seelev has recently 

 published a paper in the Philosophical Trans- 

 actions upon The Reputed Mammals from the 

 Karroo Formation of Cape Colony, in which 

 he reconsiders the evidence as to the mam- 

 malian nature of Theriodesmus and of 

 Tritylodon. He established the former 

 genus some j'ears ago upon a fore-arm ; the 

 latter was established by Richard Owen in 

 1884, upon a skull. In his previous papers 

 the author has descrilied both of these types 

 as mammalian, and the skull has invariably 

 been placed with the niesozoic Monotremes, 

 owing to the resemblances which its teeth 

 present, both in the crown and in the multi- 

 ple fangs, to other mammals of this veiy an- 

 cient and widespread group of multituber- 

 culates. Professor Seelev, in his renewed 

 examination of the skull of Tritj'lodon, be- 

 lieves that he finds evidences of • post- 

 frontal ' and ' pre-fi'outal,' and possibly of a 

 ' transverse ' bone, as in the Theriodont 

 reptiles. This evidence he considei-s over- 

 weighs the distinctively mammalian char- 

 acters of the teeth. If it is subsequently 

 confirmed by more satisfactory material 

 this will be another example of the inde- 

 pendent development of what we have al- 

 ways considered distinctively mammalian 

 characters within the reptilian class. An- 

 other remarkable species of an undoubted 

 reptile is the Diademodon tetraijonus, in 

 which the single-fanged or reptilian molar 

 teeth are capped with crowns which bear a 

 most striking resemblance to a low-crowned 

 quadritubercular mammalian molar. These 

 discoveries in the Kai-roo Formation prom- 

 ise to yield most interesting and surprising 

 results, although if the position here taken 



