A Study iif Sonic Erüatoirvnic Ants. 



313 



Foi'niirit imll hh'-fnhut T> \ 1 1;. /v/i*. nitliJivcntris E.mkry. 



In ilititTfiit in'sts (if J'or>n/f(( Hilidiroifris' taken at Colebrook, 

 Cttiin.. by Dr. \\'iiKi;M:K tliice pcculiai- nii('rü<iynes were fuund. There 

 is a A'ery sliglit difference in tlie thoracic strncture of tlie queen 

 and these individuals. In tlie tirst two thoracic sejiinents the qneen 

 lias all the typical parts except that the epimerite and episternite 

 have fnsed. and the sutnre between these and the sternite is a little 

 less marked than is typical. In the metathorax the episternite and 

 sternite have fnsed, the metanotnni, epinotnm and epinierite are 

 distinctly separated. 



The structure of the pro- and meso-thorax of the microgyne is 

 exactly like that of the qneen. biit in the metathorax the epinotum 

 has fused witli the episternite and sternite. A very interesting fact 

 in connection with the niicrogynes is that they have returned to 

 the coloring- ot the typical srJiaxfusm Mayk. which is a bright yellow 

 althuugh the coloring of the (^ueen and workers of F. nitidiventris 

 is dark brown. 



Tlif fnllowing gives the relative sizes of the queen and niicrogynes: 



Head 



Length of 

 Thorax 1 Abdomen 



Bodv 



Thoracic 

 Thiekness! Width 



(^ueeu 

 .Microiivne 



22 



1.9 



3.9 

 2.9 



8.1 

 2.2 



51 



2.1 

 1.2 



2.2 

 1. 



(atnponotns macnffftus Fabr. snbsj). vieiiuis Mayr 

 rar. nitidiventris Emery. 



In a nest of C. )». ricinus rar. nUidirodris collected in San Jose, 

 California, by Dr. Harold Heath, two pseudogynes occnred. The 

 nest of tliis ant contained males. qiieens, soldiers and workers. 

 Tlitsc two speciniens are of the sanie size as the soldiers. from 

 which they ditter in thoracic structure mainly. The pseudogynic 

 fonns, however, are not alike. One has the same coloring as the 

 workcr. the other is very niuch darker, in fact almost black. The 

 abdoiuen is larger than that of the worker. but not nearly so large 

 as that of the soldier. 



The qneen has very nearly a tyjdcal thorax: the epimerite and 

 episternite of the mesothorax have fused, and the deniarcation 

 between these and the sternite is very slight, as is also the Separation 



