some Teratological Specimens. 175 
defect arising from the same causes, whatever they were, 
that led to the mandibular aberration. The mouth parts 
of the imago presented no trace of difference from the 
ordinary typical specimen. 
I have given in Figs. 4 and 5 outlines of the larval jaws, 
Fig. 4 of the full-grown feeding larva, and Fig. 5 of the 
estivating larva, jaws that it uses for no other purpose 
than to eat the cast skin. The differences between the 
two jaws of each pair are not altogether due to bad draw- 
ing, and not of course to any differences between the jaws 
of either side, but simply to a difference of angle of the 
specimens under the camera, It will be noticed that the 
estivating jaws are smaller than the feeding ones, and 
the pupal ones smaller still (all are to same scale, a 
magnification of 22 diameters). 
Inthe Ent. Mo. Mag., 1896, pp.54—80, I related some cases 
of larvee of Agrotis comes that became larvee with some 
pupal characters on taking the moult that would normally 
have been that to pupa. The present is the only case of 
a similar sort I have since met with. In that case the 
active cause was some delay of development owing to 
irregular starvation. In this one I do not know the larval 
history, but the specimen was the very last to pupate out 
of some 430 examples. So that, if not starvation, some 
causes delaying the progress of development must have 
been active, but produced no visible effects except that on 
the mandibles and the difficulty of emergence from the 
pupa, whatever that may have been. 
The specimen of Catocala nupta was exhibited at the 
Entomological Society on December 5th by Mr. Bacot. 
The left fore-leg has a widened and thickened tibia, with 
one tarsus almost normal and a second of smaller size 
beside it. When it came into my possession, the super- 
numerary tarsus had lost the last two joints by some 
accident, the third joint showing plaimly that they had 
existed and were not absent congenitally. I have restored 
them conjecturally on the plate. The supernumerary 
tarsus is more slender than the normal one and of about 
two-thirds its length. 
The specimen of Capnia atra is somewhat similar. In 
this case the tarsus affected is of the posterior leg. The 
tibia is normal or nearly so, but the first tarsal joint 
is much widened and carries at its broad extremity three 
second tarsal joints, each with normal third joints, claws 
