294 
Psyche 
[December 
Conclusions 
Since we first found the pygidial gland widespread in the sub- 
families Myrmeciinae and Ponerinae, we speculated that this gland 
might be a primitive monophylogenetic trait in ants generally 
(Holldobler and Haskins 1977). The results reported in the present 
paper fully confirm this assumption. A well-developed pygidial 
gland was found in the most primitive ant, Nothomyrmecia ma- 
crops, and in representatives of all major subfamilies except in the 
Formicinae (Table lb). We agree with Kugler (1978) that the “anal 
glands” of the Dolichoderinae and Aneuretinae are homologous to 
the pygidial glands of other ant subfamilies. Considering the 
variation in the morphology of the pygidial glands, even within a 
single subfamily, we think that the morphological variation of the 
“anal glands” of dolichoderine and aneuretine species does not 
warrant a separate terminology. In fact the term “anal gland” is 
misleading, because the glands do not exit from the anal opening of 
the gaster, as is sometimes inferred, but between the 6 th and 7 th 
abdominal terga (Fig. 28). This was clearly demonstrated by Pavan 
and Ronchetti (1955). It is our view and also Kugler’s (pers. 
communication) that the “anal glands” should be called pygidial 
glands. 
Kugler (1978) concluded from his comparative studies of myrmi- 
cine species that usually those species that have reduced or modified 
stings also have well-developed pygidial glands. He assumes that the 
pygidial gland replaces the sting apparatus as a chemical defense 
device. Our finding that well-developed pygidial glands occur in 
Pogonomyrmex, a genus with a very effective sting apparatus, and 
in many stinging ponerine species, does not support Kugler’s 
conclusions. 
Acknowledgements 
This paper would not have been possible without the help of 
many people. We would like to thank all the collectors mentioned in 
Table 1, including Donald W. Windsor, who helped finding the 
acacias in the Canal Zone. Special thanks to Robert W. Taylor, who 
sent us the precious Nothomyrmecia. Barry Bolton, William L. 
Brown, Jr., William H. Gotwald, Jr. and Roy Snelling identified 
many species for us. We are grateful to Ed Seling for his superb 
assistance during the SEM work. Frank M. Carpenter’s many 
suggestions improved the manuscript greatly. This work was sup- 
ported by NSF grant BNS 77-03884. 
