237 



NOTICES OF BOOKS. 



Contributions to the Biology of the Danish Culicidae. 



By C. Wesenberg Lund. pp. 210 + 21 plates + 19 figs. 



in text. 10| inches X 8| inches. {Memoirs of the Royal 



Academy of Sciences.) (Copenhagen : Andr. Fred Host & 



Son, 1920-21.) 

 Dr. Wesenberg Lund in his introduction to the above monograph 

 makes the following statement with regard to the methods of 

 reseaxch to be followed : "He who has first crammed his head 

 with all that has been written upon a subject will at the moment 

 of observation, when standing face to face with nature, soon under- 

 stand that his whole learning is only felt as a burden and restricts 

 his power of observation. I for my own part have always been 

 of the opinion that it is exactly the smallest equipment of human 

 knowledge which gives the greatest peace in my studies, creates 

 the scientific sovereignty over observation and thought, and — • 

 as far as possible — moves the milestones of time nearer to the 

 borders of eternity." This seems a counsel of perfection hard 

 to follow under modern conditions of work. For if we are not to 

 benefit by the pioneer work already done in any subject, the years 

 may find us laboriously cutting tracks through regions of 

 knowledge already explored and mapped by the early workers. 



The author's researches into the life-history of the Danish 

 Culicidae, which were carried out during several years, involved 

 the description of the anatomical details of the larval forms and 

 keeping them under observation in specially devised tanks in 

 the laboratory. By this means he was able to reach definite 

 conclusions not only as to the interrelationship between the larval 

 forms and imagines, but also to prove that some of the species 

 (4) living in Denmark were of American origin and had not 

 hitherto been recorded from Europe. Not the least interesting 

 result of his researches, and one that gave him great delight 

 and was of prime importance, was the presence of the tropical 

 form Taeniorhyncus, which by its mode of respiration — with 

 its siphon pierced into the tissue of the water-plants — is able to 



