510 Mr. H. Eltringham on 
a protection against the attacks of the ants by which in 
life it is surrounded. The entire skin is covered with thick 
chitinous plates which are irregularly radiate, and have 
sloping edges. The projections of these plates interlock 
with the lateral cavities of those adjacent, and the appear- 
ance under a high power is not unlike that of a complicated 
armour sheet of cog-wheels. Such an arrangement doubt- 
less provides a very efficient protective covering with a 
maximum of flexibility. One of these plates is shown 
highly magnified at fig. 7, but they vary considerably in 
size and in the extent to which the edges are sloped. 
Further microscopic examination shows that the brown 
markings on the larva are caused by the presence of small 
brush-like chitinous tufts, fig. 8, one of which arises from 
the socket in the centre of each chitinous plate. In the 
unpigmented parts of the skin, from which these tufts are 
absent, the plates still have the sockets, so that at one 
period of its evolution the larva probably had the tufts 
or at least some scale-like growth on every plate. Here 
and there in the armour, especially (probably exclu- 
sively) * on the pigmented areas, there are small round 
openings, the edges of the adjacent chitinous plates being 
neatly hollowed so that each forms its respective part 
of the circle. Possibly these apertures are the external 
openings of glands, though I have as yet no proof of this. 
If, as I think, they are confined to the pigmented areas, 
this would probably account for the correlated presence 
of the brush-like tufts, which may either protect the 
openings, or, as Prof. Poulton has suggested, hold some 
attractive secretion prized by the ants. 
Fig. 5 shows a portion of the margin of the mantle. 
The extreme outer edge is armed with a regular fringe 
of flat chitinous projections, their bases furnished with 
interlocking processes. On the upper side of each pro- 
jection there is a thin scale, very narrow at its socket but 
increasing outwardly to about the same width as the 
projection on which it lies. The purpose of these scales is 
not very obvious, but possibly they may have a tactile 
function. Within the peripheral fringe so formed there 
is a row of thick elongated chitinous plates, the edges of 
* The openings described can be seen only in a carefully made 
microscopic preparation, and proof that they occur on the pig- 
mented areas alone could only be obtained by making preparations 
of the skin of the entire larva. 
