94 THE entomologist's record. 



emergence, present a striking appearance, the gaster assuming a bright 

 orange colour. Forel, to whom I sent some ^ s, named them as above. 

 He says in his letter " .... it has the head brown in front, and 

 reddish behind, which brings it very close to a slight variety which 

 I have called tubero-mterriipttin, because the character of its colour 

 brings it near to inten-Kptiis, We consider the forms nnifanciatus, 

 interritptKs, nirp-iceps, and a/pnis, as sub-species of tnhcruiti in spite of a 

 considerable difference, precisely because of numerous bastard or inter- 

 mediary forms found between them." 



It will be seen from my description that the sole difference from 

 tuberum {s.str.), is in the coloration of the head, which in tuberum (s.str.), 

 is entirely dark, except in occasional specimens. The 3' and $ of 

 this variety, however, show rather more distinct differences, but it can 

 only be considered a very slight variety of tuberum (s.str.). 



ForeP^ gives the following intermediary forms as occurring in 

 Switzerland : — nylandero - corticaUs ; nylandero - unifasciatus ; tubero- 

 ninriceps ; tubero-affinis ; tub er o- inter rupti is ; unifasciato-interruptus. 



Thorax finely rugose. Spines narrow, long, about two-thirds as long as the 

 basal face of epinotum, and slightly curved. 



Yellow or reddish -yellow ; club of antenna*, front of head, but not vertex, and 

 often an indistinct patch on the base, and extending up the sides, of the top of 

 first segment of gaster, dark brown. 



L., 2mm.-2-3mni. Sub-sp. interruptus, Schenck. 



This sub-species is new to the British Isles. It was found by 

 Donisthorpe and myself at Beaulieu Road, New Forest, in July, 1912. 

 There were numerous colonies, many containing ^ s and winged ? s, 

 and the nests were either alone in the earth, or actually in the sides of 

 nests of Tetrmiwrium caespitum. A solitary deiilated ? was found in 

 the earth of a nest of the latter species. Judging from the experiment 

 of placing colonies of the two species together in an artificial nest, I 

 conclude that though not actively hostile, the Tetramorium and Lepto- 

 thorax avoid contact with each other as much as possible. The latter 

 may find protection in their proximity to the more powerful and 

 populous colonies of Tetramorium.. 



As stated above, Forel named these ants " tuberum. var. tubero- 

 al^.nis," but after examining the <? s, and comparing them with draw- 

 ings and descriptions kindly supplied by Emery and Forel, and also 

 with the interruptus $ in the Saunders' collection in the British 

 Museum, presented by Schenck, I have no doubt that they are true 

 interruptus, Sch.* 



Thorax finely rugose. Spines about one half as long as basal face of epinotum. 



Yellow ; front of head and club of antennae red or reddish brown ; a clearly- 

 defined band across the base of the first segment of gaster, dark brown, the top of 

 the segment bright yellow. 



L. 2-5mm.-3-5mm. . . . Sub-sp. unifasciatus, Latr. 



Although not yet found in Britain, I have included this sub- 

 species in order to emphasize its difference from tuberum (s.str.). The 

 clear-cut dark band on the gaster, standing out against the bright 

 yellow above it, at once distinguish unifasciatus from any of the others. 



w loc. cit., p. 86. 



* Bondroit, to whom Donisthorpe sent some specimens, considered them to be 

 interruptus, Sch. 



