670 



SCIENCE. 



[N. 8. Vol. XX. No. 516. 



protection. In Texas, however, cotton is 

 grown under a great variety of conditions. 

 The climatic vicissitudes of heat and cold, 

 drought and flood are many times as great 

 as in Guatemala, so that notwithstanding 

 the unexpectedly great adaptability of the 

 kelep it can not be expected to thrive 

 equally well in all parts of the state, any 

 more than does the weevil. Even if it be 

 found that the ants can thrive, breed and 

 establish new colonies in Texas, they will 

 probably require many years to take full 

 and effective possession even of the more 

 favorable localities of this vast agricultural 

 empire. Such a mitigation of the weevil's 

 injuries would be, of course, of great prac- 

 tical value, and the work of the ants in 

 destroying the larvae of boll worms and 

 leaf-worms might be only slightly less im- 

 portant in some districts. If, however, the 

 hope of exterminating the weevil is to be 

 cherished, or that of staying its ravages 

 before it has laid the entire cotton industry 

 of the South under tribute, there would 

 seem at present to be no other alternative 

 than to secure by discovery or development, 

 within the next few years, a variety of cot- 

 ton in which the larvse of the boll weevil 

 can not mature. 



The present brief outline of the results 

 of our study of cotton in Guatemala may 

 be summarized by saying that the tendency 

 to rapid growth and early fruiting, the 

 large extrafloral nectaries which attract 

 the ants, and the proliferation of the tis- 

 sues of the young buds and bolls which 

 kills the weevil larvae, are protective ad- 

 aptations, developed as a result of long 

 contact between the cotton plant and the 

 boll-weevil. The proliferation is not a' 

 mere pathological abnormality, but repre- 

 sents a definite evolutionary tendency, ca- 

 pable of further increase by selection. If 

 this interpretation of the facts be correct 

 it affords an intimation of a successful 



solution of the weevil, problem by means 

 of a resistant variety of cotton. 



0. F. Cook. 

 Washington, November 4, 1904. 



SCIENTIFIC BOOKS. 

 Dr. J. Frick's Physikalische Technik oder 

 Anleitung zu Experimentalvortragen sowie 

 zur Belbstherstellung einfacher Demonstra- 

 iionsapparate. Siebente vollkommen um- 

 gearbeitete und stark vermehrte Auflage 

 von Dr. Otto Lehmann. Friedrieh Vieweg 

 und Sohn. 1904. Pp. xxiii + 630. 

 The previous edition of this well-known 

 standard work appeared in 1890-5 and con- 

 sisted of two volumes, one of 725 pages, the 

 other of 1,054. It is most interesting to note 

 that there exists such a demand for a book 

 of this character as to encourage the publish- 

 ers to undertake the present seventh edition 

 on such an enormous scale. This is to con- 

 sist of two volumes ; and of these the first part 

 of the first volume only has so far appeared, 

 having- been published during the past sum- 

 mer. This is a volume of 630 pages and is 

 illustrated with over 2,000 cuts. The scope 

 of the present work as compared with pre- 

 vious editions may be estimated when it is 

 noted that the subject matter contained in 

 the volume under review had devoted to it in 

 the last edition only 132 pages and 65 cuts. 

 As the title of the work indicates, it has 

 a twofold object : one to suggest suitable ex- 

 periments for class demonstrations, the other 

 to give accurate instruction in the use of in- 

 struments, tools and technical methods. The 

 subtitle of the first part of the first volume is 

 ' The Rooms of a Physical Laboratory and 

 their Equipment, together with an Introduc- 

 tion to the Use of the Latter.' There are five 

 chapters : (1) ' Physical Demonstrations and 

 the Laboratory Building'; (2) 'The Large 

 Lecture Room'; (3) 'The Preparation Room 

 and the Smaller Lecture Room ' ; (4) ' The 

 Rooms for Apparatus and Assistants ' ; (5) 

 ' The Rooms for the Mechanician and Jani- 

 tor.' 



There are numerous subdivisions of the 

 chapters and full information is given in 

 regard to almost every conceivable detail. 



