INADEQUACY OF NATURAL SELECTION, ETC. 687 



to occur is real, and not due to the selection by the ants of an individual 

 that though appearing to our eyes undifferentiated is not really so. This is 

 that an individual can be made into a soldier after it has visibly undergone 

 one half or more of the development into a winged form. The Termites 

 can in fact operate on an individual that has already acquired the rudi- 

 ments of wings and whose head is totally destitute of any appearance of 

 the shape of the armature peculiar to the soldier, and can turn it into a 

 soldier ; the rudiments of the wings being in such a case nearly entirely 

 re-absorbed." 



Grassi has been for many years engaged in investigating these 

 phenomena, and there is no reason for rejecting his statement. 

 We can scarcely avoid accepting it, and if so, Professor Weis- 

 mann's hypothesis is conclusively disposed of. Were there 

 different sets of " determinants " for the soldier-form and for the 

 winged sexual form, those " determinants " which had gone a 

 long way towards producing the winged sexual form, would in- 

 evitably go on to complete that form, and could not have their 

 proclivity changed by feeding. 



[Yet more evidence to the like effect has since become known. 

 At the meeting of the Entomological Society, on March 14, 1894 

 (reported in Nature, March 29) : 



"Dr. D. Sharp, F.R.S., exhibited a collection of white ants (Termites), 

 formed by Mr. G. D. Haviland in Singapore, which comprised about twelve 

 species, of most of which the various forms were obtained. He said that 

 Prof. Grassi had recently made observations on the European species, and had 

 brought to light some important particulars ; and also that in the discussion 

 that had recently been carried on between Mr. Herbert Spencer and Prof. 

 Weismann, the former had stated that in his opinion the different forms of 

 social insects were produced by nutrition. Prof. Grassi's observations showed 

 this view to be correct, and the specimens now exhibited confirmed one of the 

 most important points in his observations. Dr. Sharp also stated that Mr. 

 Haviland found in one nest eleven neoteinic queens that is to say, individu- 

 als having the appearance of the queen in some respects, while in others they 

 are still immature." 



Another similarly conclusive verification I published in Nature 

 for December 6, 1894, under the title "The Origin of Classes 

 among the ' Parasol ' Ants." The letter ran as follows : 



" Mr. J. H. Hart is Superintendent of the Royal Botanic Gardens in Trini 

 dad. He has sent me a copy of his report presented to the Legislative Coun- 

 cil in March, 1893, and has drawn my attention to certain facts contained in 

 it concerning the 'Parasol' ants the leaf-cutting ants which feed on the 

 fungi developed in masses of the cut leaves carried to their nests. Both Mr. 

 Bates and Mr. Belt described these ants, but described, it seems, different, 

 though nearly allied, species, the habits of which are partially unlike. As 

 they are garden-pests, Mr. Hart was led to examine into the development and 

 social arrangements of these ants ; establishing, to that end, artificial nests, 

 after the manner adopted by Sir John Lubbock. Several of the facts set 

 down have an important bearing on a question now under discussion. The 

 following extracts, in which they are named, I abridge by omitting passages 

 not relevant to the issue : 



" ' The history of my nests is a* follows : Nos. 1 and 2 were both taken 



