ALWAYS PKODUCE MALES. 39 



The nest of Formica cinerea, captured at the same 

 time, produced four larvae, all of which perished before 

 arriving at the pupa stage. The larvae of males and 

 of queens are much larger than those of workers, 

 and these larvae were too big to have been those of 

 workers. 



In a nest of Formica fusca, which I have had 

 under observation since August 1876, three pupae were 

 produced. They were all males. Another nest of 

 Formica fusca produced a single young one, which also 

 was a male. 



Lastly, my nest of Polyergus rufescens, which M. 

 Forel was so good as to send me in the spring of 1876, 

 in 1879 produced twelve pupae. Eleven of these turned 

 out to be males. The other one I lost ; and I have 

 little doubt that it was brought out and thrown away. 

 It was certainly not a worker. As regards the first 

 three of these pupa?, I omitted to record at the time 

 whether they belonged to the Polyergus or to the 

 slaves, though I have Uttle doubt that they belonged to 

 the former species. The last eight, at any rate, were 

 males of Polyergus, 



Indeed, in all of my queenless nests, males have 

 been produced ; and in not a single queenless nest has 

 a worker laid eggs which have produced a female, either 

 a queen or a worker. Perhaps I ought to add that 

 workers are abundantly produced in those of my nests 

 which possess a queen. 



WTdle great numbers of workers and males have 



