Sept. 1896.] 
Wickham : Larvae of Some Beetles. 
123 
point about five feet from the ground, an injury which had removed 
the bark, the exposed place then being attacked by the large horn-tail, 
Tremex columba. For about an inch from the surface the wood was 
quite hard, but inside of this shell was quite badly decayed and soft. 
The young Acamptus larvm were found just entering the soft wood on 
sides of the Tremex burrow, while the large ones were taken at the end 
of a gallery of an inch or two in length, this gallery having its origin 
from the side of that of the Tremex. The full grown larvae had formed, 
at the date mentioned, rounded cells, apparently for pupation; these 
cells had no evidence of silk in their construction. Mr. Wolcott has 
kindly furnished a drawing to illustrate the work of this larva (Plate 
IV, Fig. 6). The burrow of the Tremex is shown at Tr, while 
that of the Acamptus is marked Ac. The black spots in the latter 
show where the larva had made short secondary burrows for the depth 
of an eighth of an inch or so. All of the larvae taken by Mr. Wolcott 
were found with the head pointing upward, whether the burrow ran 
up or down. This may simply be the position of rest for the winter. 
A few adults were taken with the young, at the date cited, but they were 
more numerous in November preceding. None have been seen on the 
outside of the tree, nor do any of the healthy trees seem to have been 
attacked. 
Yuccaborus, sp. (Fig. 5.) 
Larva robust, natural position curved, consistence soft. Color 
nearly white, head testaceous, mouth dark brown. Head more strongly 
chitinized than the rest of the body, its upper surface sparsely bristled, 
median line distinct for about one-half of the distance from the hind 
margin when it forks, separating into two lines, one of which extends 
towards each anterior angle. Antennae extremely short and contained 
in pits at the sides of the head near the mandibles. Clypeus separated 
from the front by a distinct suture ; in form transverse, approximately, 
thrice as broad as long, narrower anteriorly, sides oblique. Labrum as 
broad as the anterior margin of the clypeus but shorter than the sclerite, 
sides rounded, bristled as shown in the figure. Mandibles extremely 
heavy, triangular in outline, the inner margin irregular but without de¬ 
fined teeth. Maxillae with very heavy base, inner face flattened and 
armed for about one-half of its length with a dense covering of bristles. 
Palpi two-jointed, the first joint much stouter than the second. Labia 
palpi two-jointed, almost like the maxillary ; the ligula is emarginate at 
tip, and each of the projections thus formed bears a bunch of bristles at 
apex. Prothorax about as long as the meso- and meta-thorax combined, 
