DR. TIIEODOU NEUMANN. 247 



where they find ways and means of being taken up by 

 another intermediate host, i.e.y ^yhere the latter lives and 

 gathers its food. There they hang on leaves, on grass, 

 lie on the ground, stick then to the skin and feet of the 

 animal and find thus ample opportunity of being trans- 

 ported into the mouth and from there into the alimentary 

 canal. 



These discoveries have all been made within a compar- 

 atively recent period, and would not have occurred to any 

 one in former years; still a good deal of investigation 

 remains to be done. What we know now about parasites 

 is only the frame-work of the whole structure of knovel- 

 ege. We lack yet very many of the details. It will be 

 necessary indeed to continue untiring observations and 

 researches, to add stone after stone to the glorious build- 

 ing of truth which is being erected by hundreds of 

 faithful workers. Then only can we think of solving 

 the many other questions of our "helminthology," of 

 studying not only the anatomy and embryology of the 

 parasites, but also the whole sum of conditions which 

 exist between their different representatives, between 

 them and other animals, between them and their hosts, 

 between them and their way of living — truly a large 

 and extensive territory! However, the beginning is 

 made, and we have a right to hope that it will have a 

 successful continuation. And just this recognition of 

 what is still to be done may teach us how hasty and 

 wrong the conclusion is that we have accomplished 

 everything we wanted to know and to do. No doubt we 

 have a right to say, when we look upon that has been 

 accomplished: "Well done, good and faithful servants!" 

 Nevertheless, let us look ahead and keep in mind that 

 we have only stepped over the threshold of the temple 

 of science, that we have not yet advanced into the Holy 

 Place,and that the curtain which hides the most precious 

 facts of truth has not yet been withdrawn. In 1780 a 



185 



