July 13, 1906.] 



SCIENCE. 



55 



The Grignard reaction, since its discovery 

 a few years ago, has been extremely productive 

 of valuable results and appears to be capable 

 of rendering service in this case also. An 

 ingenious application of it, described recently 

 by J. Houben,^ constitutes an important ad- 

 vance towards the solution of the general prob- 

 lem described above. The process consists 

 of the following stages : Magnesium, an alkyl 

 haloid and absolute ether are allowed to react 

 in the ordinary manner, to give the Grignard 

 reagent; if ethyl chloride is employed the 

 action may be represented by the equation: 

 Mg + 0,H,01 -^ MgClC,H,. The ethylmag- 

 nesium chloride is mixed with the alcohol to 

 be experimented with and there results a 

 hydrocarbon and magnesium alkyloxy chlo- 

 ride; with tertiaryh-aijl alcohol the reac- 

 tion would be: C,H,MgCl+(CH3)3COH-> 

 (CH3)3COMgCl + C,H,. The ethane, of 

 course, escapes. The last step consists in 

 adding acetic anhydride to the above product, 

 which results in the formation of tertiary- 

 butyl acetate and magnesium acetochloride : 



(CH3)3COMg -f (CH3C0),0 -> 



(CH3)3COCOCH3 -f 0H3C00MgCl. 



The preceding method has already led to 

 the synthesis of a variety of acetates of 

 geraniol and of terpin series, such as terpin 

 diacetate; the resulting compounds are closely 

 allied with some of the odoriferous materials 

 of plants, and their further study promises re- 

 sults of importance and value. The method 

 also gives good service in the esterification of 

 phenols. 



Benzylmagnesium chloride, OgHjCIT^MgCl, 

 may be used in place of the ethyl derivative, 

 but curiously enough, the corresponding bro- 

 mides or iodides can not be employed; with 

 the former the yield is poor and with the 

 latter the reaction is practically inhibited, ex- 

 cept in the case of saturated alcohols, for 

 which, however, the bromides are preferable. 

 The results of a more extended investigation 

 of this subject will be awaited with interest. 



J. Bishop Tingle. 

 Johns Hopkins Univeesity. 



^Ber. d. Chem. Ges., 39, 1736 (1906). 



RECENT VERTEBRATE PALEONTOLOGY. 



Extinct Mammals of Patagonia. — The third 

 part of the first volume of the Annates de 

 Paleontologie under the direction of Dr. Mar- 

 cellin Boule, professor of paleontology in the 

 Museum of Natural History of Paris, has 

 just been received. It contains the conclusion 

 of Professor Albert Gaudry's review of the 

 fossils of Patagonia, in which this distin- 

 guished paleontologist presents the most clear 

 and interesting account of the mammalian 

 life, especially in the Eocene, Oligocene and 

 Lower Miocene. Summaries of the geolog- 

 ical results obtained by Hatcher, Ortmann, 

 Tournouer, are given, together with a discus- 

 sion of the environment of the remarkable 

 succession of mammalian life. This is by far 

 the clearest and most interesting presentation 

 we have yet had of the development of this 

 peculiar fauna. The author is a strong be- 

 liever in the existence of an Antarctic conti- 

 nent; in fact he regards this fauna as the 

 fauna of such a continent. He observes that 

 Patagonia serves to give us a clear idea of its 

 geographical extent by its climate, remarking 

 ' that if Patagonia is not a part of an Ant- 

 arctic continent its paleontological history is 

 altogether incomprehensible.' It is interesting 

 to contrast this statement with one recently 

 made to the writer by Sir John Murray to 

 the effect that he found no evidence whatever 

 sufficient to convince him even of the existence 

 of such a continent. 



Eocene Mammalia of Northern Africa. — ■ 

 By far the most important paleontological 

 event of recent times was the discovery in 

 1900 of the ancient fauna of the Fayum. 

 This is the lake province of Egypt, a district 

 occupying a depression in the desert to the 

 west of the Nile Valley opposite Wasta, a 

 small town about fifty-seven miles south of 

 Cairo. Erom time to time since this dis- 

 covery Messrs. Beadnell, of the Egyptian Geo- 

 logical Survey; Dames, of Berlin; Stromer, 

 of Munich; Eraas, of Stuttgart, and especially 

 Andrews, of the British Museum of Natural 

 History, have been presenting short contribu- 

 tions to our knowledge of this fauna. We 

 have now received ' A Descriptive Catalogue 



