1935] 
Australian Ant Genus Mayriella 
155 
half times as long as broad, joints 2-6 twice as broad as 
long, the seventh distinctly longer, the eighth slightly 
broader than long, one-third as long as the more swollen ter- 
minal joint. Thorax less than twice as long as broad; pro- 
mesonotum excluding the neck narrower than the head, sub- 
trapezoidal, anteriorly twice as broad as posteriorly, with 
feebly rounded anterior and nearly straight, marginate 
anterior and lateral borders ; in profile rising rather 
abruptly from the neck, moderately and evenly rounded 
above, slightly sloping behind to the short, feebly costate, 
transverse mesoepinotal groove or impression ; base of 
epinotum quadrate, sloping with slightly raised anterior 
border and marginate sides, the marginations enlarging 
below to form a pair of small, blunt, flattened teeth, which 
are shorter than their basal diameter; epinotal declivity 
much shorter than the base, continuing down in the same 
sloping plane between the metasternal lobes. Petiole but 
little longer than broad, narrowed anteriorly, its node 
broader than long, subrectangular, with straight, trans- 
verse anterior border and straight, parallel sides; in pro- 
file subcuneate, higher than long, with straight ascending 
anterior slope, meeting the shorter, evenly convex posterior 
slope at a distinct angle ; ventral surface of petiole straight 
and horizontal, the tooth at its anterior end blunt and 
translucent. Postpetiole from above nearly one-third 
broader than the petiole, one and one-half times as broad 
as long, rounded-oblong; in profile broadly rounded above, 
ventrally slightly convex in the middle. Gaster about as 
large as the head, convex above and below, its anterior 
border concave in the middle, its anterior corners mar- 
ginate on the sides. 
Shining; head, thorax and petiole more subopaque; man- 
dibles smooth, sparsely and very finely punctate; sides of 
clypeus transversely rugulose, its elevated median plate 
smooth and shining. Head, thorax, petiole and ventral 
portion of postpetiole very finely and microscopically, the 
scrobes, neck, pleurae, posterior surface of epinotum, the 
petiole and ventral portion of the postpetiole more coarsely 
and evenly reticulate; front of head also feebly, longitu- 
dinally rugulose, its posterior corners and the promesono- 
