304 B. GRASSI AND A. SANDIAS. 
1. The thoracic and abdominal terga (fig. 17). The latter, 
however, exhibit an immaculate longitudinal median vitta and 
a similar rounded spot on either side. The vitta may or may 
not be evident on the metathoracic, and is wanting on the 
mesothoracic tergite; it is present on the pronotum, where it 
forms a cruciform mark with a similar transverse vitta towards 
the apex. As a rule the side margins of the pronotum are 
also immaculate. 
2. The lateral limb of the abdominal sternites; but a few 
black spots may also be seen to exist over the median portion. 
3. The thoracic pleurze (side-pieces). 
4. The basal portion of the legs. 
It is important to notice that completely yellow examples 
may at times have the wing-rudiments more developed than in 
those with brown markings, although the greater abdominal 
development, or their known history, may show the latter to 
be the older. 
The wing-pads are dirty white and exhibit abundant trachez, 
arranged as in the fully formed wing. 
Hairs are distributed everywhere except on the interseg- 
mental spaces. As I have already said, those on the abdomen 
are longer and transversely directed (figs. 17 and 18), and thus 
distinguish these forms from those in which the wings are 
fully developed (fig. 12). The genital appendices are always 
absent in the female. 
The abdominal hairs and black maculation furnish 
characteristic points of difference from the fully 
winged forms. The latter are found to become black by 
uniform darkening,—that is, without first presenting the black 
spots peculiar to the complementary or substitute examples. 
The number of antennal joints in this latter group of royal 
forms is variable, and may differ on each side of the head ; it 
may be 14, 15, 16, or 17; but the last number is exceptional. 
In no case are the antenne intact, as the examination of the 
last joint as well as the third and fourth shows (PI. 17, fig. 29). 
I have found queens without indication of wings and with 
sixteen-jointed antenne, which were obviously truncated at the 
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