208 
Psyche 
[October- December 
Dissection of a number of Diacamma workers and especially 
of the mating worker supports the inference that only one indi- 
vidual in a colony assumes the reproductive function at a time. 
Unfortunately the material had been in rather weak alcohol for 
several months and the very hard chitinous integument of the 
gaster had prevented penetration, so that the internal organs were 
considerably decomposed. In many of the workers, of which more 
than 20, belonging to three colonies, were dissected, no ovaries 
could be detected. In one, however, two ovarioles were clearly 
seen, each of the type figured by Miss Holliday (1903, Fig.Ab, p. 
295) for the ergatoid queen of Lobopelta elongata, i.e. with a large 
number of very small ova separated by clusters of nurse-cells. 
Such undeveloped ovaries were probably present in all the speci- 
mens but could not be detected on account of defective preser- 
vation. This may also explain our inabilit}'- to find a sperma- 
theca in any of these individuals. Fortunately the mating 
worker was in a somewhat better state of preservation. The 
ovaries were found very far forward, in the large first gastric 
segment and applied to the sides of the crop. There were five 
ovarioles in each ovary and the lowermost egg in each ovariole 
was fully developed and of an elongate-oblong shape, as in some 
other Ponerinse (Pachycondyla, Lobopelta). The vagina and a 
large spermatheca attached to its dorsal wall were filled almost to 
bursting with compact masses of spermatozoa. 
For some time evidence has been accumulating to show that 
Diacamma is not the only ant genus in which the winged queen has 
been lost and her function in the colony usurped by a fertile 
worker. The senior author, in the paper above mentioned (1915b, 
p. 337), called attention to the fact that winged females do not 
exist in the Ponerine genus Rhytidoponera, which is represented 
by a number of species in the Australian and Papuan Regions. 
The same condition very probably obtains also in the South 
African Streblognathus and Ophthalmopone and in the Neotro- 
pical Dinoponera, all genera belonging to the same subtribe as 
Diacamma (Pachycondylini). He also stated in his monograph 
of the Australian honey-ants of the Dolichoderine genus Lepto- 
myrmex ( 19 15a,p. 260) that true queens are in all probability absent 
