128 DoBsoN^ on Laap, or her p. 
In this examination the points to which attention was 
more particularly directed were — 
1. The structure of the yellow conical crusts. 
2. The chemical reactions of the substance of which they 
are composed. 
1. The general appearance of the crust is that of a 
more or less conical dome^ the apex of which is usually 
excentric. The surface is covered with long, shaggy, hair-like 
fibres, and the whole is of a canary-yellow colour and 
brilliant appearance, like that of spun glass or sugar. The 
cup is very loosely attached to the inferior surface of the 
leaves of a species of Eucalyptus, and the substance is very 
brittle. A portion placed on the tongue affords a sweetish 
taste. 
The texture of the crust, examined under a low power, very 
closely resembles that of the sugar-baskets made by confec- 
tioners, and the mode in which it is constructed would appear 
to admit of explanation upon the supposition that the larva 
throws out loop over loop of a glutinous material much in 
the way that an artist in glass constructs his fragile toys 
(fig. 8) . The insect, however, follows a definite plan in its 
operations ; for the edge of the limpet-shaped crust is pretty 
regularly dentated, the dentations being all very nearly of a 
length. From the point of each dentation two divergent 
branches arise, which meeting with those springing from 
the adjoining dentations, a second dentation opposite the 
interval between those of the former row. In this way 
more or less regular reticulations are formed, across 
which slender threads of the same substance are drawn 
in the most irregular manner. This structure is also 
shown in fig. 8. The older or more central part of the dome 
is thickened by subsequent deposition, and the interstices in 
this way become nearly filled up. The outer surface of the 
cone is beset with numerous long, curved, hair-like processes 
of a very curious conformation, and one not very easily 
accounted for. Each hair, which in length may equal the 
semidiameter of the cone, arises abruptly from one of the 
thicker trabeculse, and is of pretty uniform diameter through- 
out. Its surface, however, difiers very remarkably in diflPerent 
parts. Towards the point (fig. 9 a) it presents a moniliform 
appearance, and is otherwise smooth and polished ; and in 
this part it is usually somewhat compressed. This condition 
exists for about one sixth of the length of the hair. In the 
remaining portion the surface is marked by fine longitudinal 
