MYRMICA. 131 



In this specimen the scape of the left antenna (male) is longer 

 than in typical scabrinodis male, and the tooth on the right antenna 

 (worker) is large, it therefore comes near to the var. sabuleti 

 Meinert. 



Wheeler 24 records the capture of three pterergates in a small 

 colony of a form of Myrmica scabrinodis at Bronx ville, New York, 

 on September 5th, 1904. This colony comprised about 150 workers 

 and a dealated female of rather small size. Three of these workers 

 bear vestiges of anterior wings but are in every other respect 

 perfectly normal individuals. In the structure of the thorax, 

 there is not the slightest approach to the female type. Each of 

 the three specimens represents a different condition in the develop- 

 ment of the wings. In one the wing vestiges are nearly 1-7 mm. 

 long, spatulate in outline and very slender at their bases where 

 they are furnished with small but distinct tegulae. The appendages 

 are yellowish brown, translucent and covered with minute hairs 

 like those on the normal wings of females, but without any traces 

 of venation. In another worker the wings are barely '4 mm. in 

 length and are merely little opaque pads or sacs, without even a 

 trace of hairs on their surfaces, although they have minute tegulae 

 at their bases. In the third specimen the wings are even more 

 vestigial, the right being represented by a small nodular appendage 

 and its tegula, the left by a minute papilla. Keys found in a colony 

 of scabrinodis at Yelverton, in August, 1913, in which a typical 

 dealated female and males were present, a worker which is a little 

 larger than the other workers from the same nest, measuring 5 mm. 

 in length (the latter being from 4'5 to 4*8 mm. long) the head is 

 rounder and more the shape of a female, and the thorax a little 

 higher, but otherwise that of a normal worker. Two minute 

 chitinous nodules are present on each side of the mesothorax 

 anteriorly. 



In July, 1913, I found a form of scabrinodis at Rannoch, in two 

 nests of Formica rufa v. alpina, inhabiting part of the latter's 

 hillocks, but only workers and larvae were found. The scape of 

 the antennae exhibits a slight transverse ridge (more developed in 

 some specimens) reaching across from the lateral tooth, and 

 forming a small point, or angle, opposite to the same. These 

 specimens probably come near the variety scabrinodo-lobicornis 

 Forel, their colour however being that of normal scabrinodis. 



I have taken the Aphids Forda formicaria Heyden, F. viridana 

 Buckton, Schizoneura corni F., Trama troglodytes Heyden, T. 

 radicis Kalt., Brysocrypta lactucaria Pass., B. ranunculi Kalt., 

 and Tetraneura ulmi Geoff., in scabrinodis nests. 



The undermentioned myrmecophiles have occurred with this 

 species in Britain 35 : 



Coleoptera : Atemeles emarginatus Pk., Myrmedonia limbata 

 Pk., Drusilla canaliculata F., Homalota analis Gr., Staphylinus 



