SUM MUM BONUM 7 



micrococci of Malta fever by goats, and Looss's 

 discovery of the stereotropism or contact require- 

 ments of the larva of the tunnel worm (Anchylo- 

 stomum) — all of these are of primary hygienic 

 importance. 



So much however cannot be said convincingly 

 of purely morphological researches. The origin 

 of the human race, the ancestry of vertebrates, 

 the correct systematic position of fleas, 1 and 

 other cognate problems perennially awaiting solu- 

 tion, are matters of no importance in domestic 

 life, and it is hard to believe that they ever 

 will possess any such value. Although it may 

 be true that to the individual worker it is the 

 summum bonum when his science overtakes a 

 human need, it does not follow that we must 

 accept the theory that every scientific fact will 

 sooner or later directly and materially benefit 

 mankind at lar^e, and that this consideration 

 should be the guiding motive of scientific 

 investigation. Many precious facts have been 



1 For an account of a group of wingless Diptera to which fleas 

 do not appear to be related except by convergence, and the 

 amusing controversy to which it gave rise, the following papers may 

 be consulted : — I. F. Dahl, " Puliciphora, eine neue, flohahnliche 

 Fliegengattung," Zool. Anz., 1897, pp. 409-412 ; translated by E. E. 

 Austen in Ann. Nat. Hist, (vii.) I. pp. 99-101, 1898 (Puliciphora, 

 a new flea-like genus of Diptera.) 2. B. Wandolleck, " 1st die 

 Phylogenese der Aphanipteren entdeckt?" Zool. Anz., 1898, pp. 

 180-182. 3. F. Dahl, " Uber Puliciphora lucifera," Zool. Anz., 1898, 

 p. 308. 4. B. Wandolleck, ' ; Die Stethopathidse eine neue fliigel 

 — und schwingerlose Familie der Diptera," Zool. Jahrb. Syst., xi., 

 1898, pp. 412-441. 



