1930] 
A New Parasitic Crematog aster 
55 
A NEW PARASITIC CREMATOGASTER 
FROM INDIANA 
By William Morton Wheeler 1 
For many years I have suspected that some of the species 
of the huge, cosmopolitan ant-genus Crematogaster might 
prove to be social parasites. My grounds for this suspicion 
were the fact that one common Neotropical form, C. 
(Orthocrema) limata F. Smith subsp. parabiotica Forel 
commonly lives in parabiosis with Camponotus ( Myrmo - 
thrix) femoratus Fabr. and Dolichoderus ( Monads ) para- 
bioticus Forel, and the fact that the females of certain sub- 
genera, notably those of Crematogaster sens. str. (as shown 
in the type of the genus, C. acuta Fabr.), Nematocrema and 
Atopogyne, have small subtriangular gasters like those of 
the workers and unlike the voluminous, suboblong gasters 
of the females in other subgenera. This small size and 
worker-like aspect of the female gaster is, of course, a sign 
of underdevelopment of the ovaries and an indication that 
the female may be parasitic, or in other words, adapted to 
invading and securing adoption in a flourishing colony of 
some allied species in order to provide for the maturation 
of her ovarian eggs and the rearing of her offspring. 
That a parasitic Crematogaster has probably been found 
at last, not in the tropics but in our own country, is sug- 
gested by a study of some specimens sent me for identifica- 
tion by Professor C. H. Kennedy. They comprise 43 
workers and 7 black winged females which undoubtedly be- 
long to a form of our common acrobat ant, Crematogaster 
( Acrocoelia ) lineolata Say (near var. cerasi Fitch, but 
darker), together with 14 females and six males of a dis- 
tinctly different species. The females of the latter are very 
small and have the head, thorax and pedicel red as in the 
Contribution from the Entomological Laboratory of the Bussey 
Institution, Harvard University, No. 335. 
