BY ARTHUR DENDY. 
197 
patch is made up of two triangular halves whose bases face one 
another on each side of the mid-dorsal line, while their apices lie 
over the legs and at about one-third of the distance from the mid- 
dorsal line to the insertion of the legs. The separation of the 
diamonds from one another is by no means complete, so that there 
are two continuous bands of red, one on each side of the mid- 
dorsal line, the outer margins of which bands are deeply indented. 
The edges of the mid-dorsal groove are commonly darkly pigmented, 
and may give rise to an apparently single median dark line when 
the lips of the groove are closed together. There is commonly 
also a dark edging to the red diamonds, forming a zig-zag longi- 
tudinal stripe. This typical pattern may be almost if not quite 
obliterated by the replacement of the red pigment by the dark 
indigo blue; but even in very dark specimens it may still be 
represented by a row of small, pale yellow or red spots, each 
occupying the position of the apex of one of the red triangles in 
typical specimens. The ventral surface is paler than the dorsal, 
and there is in the middle line a row of still paler areas placed one 
between the legs of each pair but the last. Patches of dark 
indigo blue are usually present on the under surfaces of the legs 
near to their bases. 
In the adult female, in place of the usual genital papilla, there 
is a very conspicuous organ which may be called an ovipositor. 
This, when contracted, is an ovoid body of a pale yellow or orange 
colour, projecting backwards from between the legs of the last 
(15th) pair. In adult specimens ordinarily contracted in spirit 
the ovipositor is as large or larger than the legs between which it 
lies. It is, however, capable of great extension. Its surface is 
uniformly ornamented with minute, spine-bearing papilla?, and at 
its apex it bears a large slit placed parallel to the long axis of the 
body of the animal. 
The internal reproductive organs of the female are arranged as 
follows : — The ovary consists of right and left halves united in 
front and behind and attached by a mesentery to the pericardial 
septum in the mid-dorsal line. The oviducts are long and con- 
voluted; they have a common origin from the posterior end of the 
