[March 
44 Psyche 
our four millimeters in diameter proves that the specimen 
is fully mature. 
Several changes in the mouthparts occur at the final 
ecdysis (Fig. 1 ; A, D) . The large, pointed, falcate mandibles 
of the larva are tapered to a point and bear a conspicuous 
groove externally on their apical third. Those of the adult 
have the apex flattened into an obliquely truncate edge 
which lies in a vertical plane so that the tip appears acute 
in ventral view and only close observation indicates that the 
mandibles undergo a quite considerable change in shape. 
The maxillary palpi are obviously shortened in the adult, 
but the actual changes are slight. The maxillae themselves 
are also shorter in the adult. The labium is changed mainly 
by the addition of another joint in the palpi. All of these 
changes in the mouthparts clearly represent a degeneration 
in functional capacity but they include also the retention to 
some slight degree of features involved in the increased 
complexity that normally characterizes the imaginal stage. 
The same is also true of the tarsi and this is of particular 
interest, since the segmentation of the tarsi is one of the 
most remarkably constant characters, among practically all 
groups of insects, and it is only slightly changed in the 
female Lamprophorus despite the inhibition of so many of 
the more conspicuous imaginal features and the absolutely 
larviform habitus. 
The accompanying figures drawn for me by Mrs. A. S. 
O’Connor illustrate the several structures to which refer- 
ence is made. 
