44 THE entomologist's record. 



Welsmannism and Entomology. 



By A. W. BACOT. 



No century number of an entomological magazine would be com- 

 plete without some reference to the work of Professor August Weis- 

 mann, and I can fully appreciate our editor's desire to have an article 

 dealing with his work. What I do not understand is why he should 

 have asked me to write it, my only qualification, so far as I am aware, 

 being that I hold Weismann's theories of heredity in preference to 

 any other with which I am acquainted. JNIy knowledge of his work 

 is largely limited to The (j-enii Pla.vn, the lecture before the Inter- 

 national Congress of Zoologists at Leyden, September, 1895, on 

 (jcriiunal Selection, and a series of experiments on different species of 

 rhopalocera, a translation of which appeared a short time since in 

 The KnUnnuloiiht. Of these last, which all entomologists must have 

 perused with interest, it is quite unnecessary to speak, but a few notes 

 on the two former may serve to recall the attention of readers of The 

 Record to the subject. 



It seems strange that work so important to zoology as a whole, by 

 an entomologist, should not have received enthusiastic welcome at the 

 hands of the general body of students of the last-named science. 

 Personally, I have found only a minority of my entomological friends 

 interested, and still fewer appreciative of the work ; while, for the 

 most part, they seemed as distrustful of these theories as primitive 

 man might be supposed to have been of fire on its first inauguration 

 as a help to mankind. There is little doubt that the study of the 

 complex problems offered by the life-cycles of the specialised insecta 

 largely influenced Professor Weismann in his theories. The puzzling 

 phenomena connected with the sharply -defined and divergent meta- 

 morphosis of some orders, the possession of a so-called neuter sex in 

 others, and the phenomena of hybridisation, demand elaborated 

 theories if they are ever to receive intelligent explanation. And it is 

 with these, and problems of similar complexity, that Weismann's 

 work will probably bear good fruit in the future, even if it only acts 

 as a stimulus to a fresh generation of workers. Personally, how- 

 ever, I should expect the main lines of Weismann's theories to form 

 the foundation of future Avork in heredity. 



The difficulties of finding stable theories (commonly called 

 " natural laws ") to fit and account for the orderly movements of the 

 heavenly bodies Avith their sIoav and slight perturbations, occupied the 

 best intellects of mankind for centuries, and even noAvadays slight 

 alterations and adjustments of the theories are needed to account for 

 the facts disco\'ered by later and more accurate obserA^ations. We can- 

 not, therefore, expect that a complete and permanent theory to account 

 for the immense range of relatively unstable phenomena arising from 

 the infinitesimal scrap of protoplasm, which is the essential factor of 

 heredity, Avill be attained Avithout generations, if not centuries, of 

 devoted labour and co-operation on the part of biological students. 

 This, howcA'cr, is no excuse for not using the tools, admittedly imper- 

 fect though they may be, supplied ready to our hands by the pioneers 

 in this branch of research, for I take it that a scientific theory is 

 essentially a tool, and its use much the same as that of any other tool, 

 i.e., as a labour-saving appliance. Even Avhen sufficiently stable and 



