130 BRITISH ANTS. 



and females leaving their nest and swarming up the grass stems 

 on the cliffs at Sandown, Isle of Wight, on August 12th, 1913, and 

 on August 14th I observed clouds of these ants flying at Shanklin. 

 Scott sent me males and females from a marriage flight, taken at a 

 height of 1000 ft. at Landridnod Wells on September 5th, 1912, and 

 Harwood winged females taken flying at Clacton-on-Sea on 

 October 12th, 1912. Wasmann often found in colonies of M. 

 scabrinodis at Exaeten, in Holland, single individual workers, 

 nearly double the usual size, with heads the shape of that of a 

 female, though relatively the size of that of a worker, the rest of 

 the body being of the usual form, and no intermediate forms were 

 present 16 . 



The same observer records the capture of an ergatandromorph 

 in a colony of this ant, also at Exaeten, in September, 1886, in 

 which a number of males and winged females were present 15 . 



It is an approximately lateral ergatandromorph with left half of the body 

 almost entirely that of a worker, whereas the right half is that of a normal 

 male. Left (worker) half of head larger than the right, opaque, coarsely 

 and longitudinally rugose, with a large yellowish red blotch above, sharply 

 delimited on the right side as far as the middle of the face, extending back 

 on the left to the middle of the side of the head as far as the first third of the 

 superior orbit, and anteriorly to the antennal insertion, which is encircled by 

 a black ring. Mandibles, antennae and left half of clypeus yellowish red, 

 the remainder of the head black. Right half of head smaller, more finely 

 longitudinally furrowed and therefore more shining (male). Right eye larger 

 (male), left smaller (worker). Ocellus lacking in that portion of the vertex 

 corresponding to the left side of the head (worker). The two remaining 

 ocelli are present, the median lying rather accurately on the boundary of the 

 black side of the head, but still entirely on that side. Right mandible male in 

 size, shape and number of teeth, but reddish yellow (worker), whereas norm- 

 ally the male mandibles are reddish yellow only at their tips. Left, much 

 more robust, mandible entirely worker. Antennae both alike, thirteen- 

 jointed, almost purely male, but very short and sparsely hairy in contra- 

 distinction to the long, abundant pilosity of the normal male antennae in 

 Myrmica scabrinodis. They are also lighter in colour, being almost uniformly 

 reddish yellow as in the worker. 



Dollman picked up a dead ergatandromorph on a path on the 

 downs at Ditchling 30 in September, 1909, which he kindly presented 

 to me, and which I have described as follows 35 : 



" Approximately lateral ergatandromorph, right half of body almost 

 entirely that of a $, the left being that of a normal $ (the left half being 

 blackish and the right reddish yellow). Right half of head rugosely striate, 

 larger than left, eye smaller ; right antennae yellow, club three- jointed ; 

 scape with strong lateral tooth at the bend ; right half of thorax yellow ; 

 epinotum with a strong spine ; right half of petiole and post-petiole yellow, 

 rugose and punctured ; right half of gaster light fuscous-yellow ; legs on 

 right side yellow, typical ^. Left side of head blackish, punctured, not 

 rugosely striate ; eye larger ; median and left ocelli present ; antenna 

 fuscous with four-jointed club ; left half of thorax blackish ; epinotum not 

 armed with a spine ; petiole and post-petiole fuscous-black, smooth ; the 

 greater part of the left half of the gaster has been eaten away, but what re- 

 mains is of a darker fuscous colour than the right. Legs on left side fuscous, 

 typical $ ; wings typical cJ." 



