FORMICA. 329 



holds it for certain that Saunders' examples belong to F. picea, 

 in which of course he is quite correct. 



F. picea Nyl. is abundantly distinct from F. gagates Latr., both 

 in structure and in habits. In the former the individuals are on 

 the average smaller, the epinotum is angled and the scale is rounded 

 ( at any rate it is never formed as in gagates, which has a scale 

 similar in shape to that of F. rufa ; I have called it hexagonal in 

 this work, and Latreille himself describes it as "squama magna, 

 ovata : margine super o medio elevato, truncate, subbidentato " 

 [Hist. Nat. Fourmis 138 (1802)] ), in the latter the epinotum is 

 quite rounded. F. picea dwells in sphagnum bogs ; F. gagates lives 

 in oak forests, nesting under large stones and at the roots of trees, 

 and attending aphides on oak trees. 



Wheeler regards gagates as an independent species, and not as a 

 subspecies of fusca [Bull. Mus. Compar. Zool. 513 (1913)], and I 



Fig. 92. 1. Thorax and scale of Formica gagates <. 

 2. ,, ,, Formica picea ^. 



(Donisthorpe.). 



consider picea also to be a good species, as it is abundantly distinct 

 from fusca in the worker, female and male, and its habits are quite 

 different ; Bondroit told me he also considered it to be a good 

 species. 



F. picea lives in wet places, and constructs small hillocks of bits 

 of cut sphagnum, grass, etc., over its nests, the whole often soaked 

 with water, and the ants and their brood living below the surface 

 of the bog. 



Nylander, as we have seen in the original description of picea, 

 records it at Helsingfors and Uleaborg " in sphagnosis," 1 and again 

 subsequently at Kuusamo " in sphagnosis." 3 



Farr en -White only states he found the ants on the open heath 22 , 

 but Arnold describes the nest found by him as follows: "When 

 collecting in the New Forest this July, a friend called my attention 

 to a peculiarly shaped ants' nest in Matley Bog. In the part in 

 which it was situated the ground was covered with tussock grass, 

 each tussock forming a little hillock from one to two feet high, the 

 ground between and below the tussocks being wet and mossy. On 



