530 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1914. 
abnormal antenna are considerably thinner than the corresponding 
joints in the normal antenna; the basal attachment of the right sec- 
ond antennal joint is much narrower than in the left, normal, antenna. 
The next molt occurred on November 18, 1911. This time I 
succeeded in saving the cast skin, which has been preserved in alcohol. 
At this molt the insect became imago. This stage is reached after 
six molts. On December 3 began the parthenogenetic egg laying. 
In this stage, the antennal tarsal joint assumed a somewhat dif- 
ferent shape, as may be seen in figure 2. The empodium had become 
reduced to a small round knob, while the claws had grown in size and 
were curved downward with strongly chitinized brown points. On 
the underside of the irregular joint, which carries the claw-like joint, 
are found four empodium-like protuberances, placed 2 and 2, and 
separated by deep furrows. Comparison of this case with similar 
ones in the other material proves that these protuberances correspond 
exactly to the paired plantula found on the underside of the first, 
second, third, and fourth tarsal joints. This irregular joimt with its 
two pairs of plantule is possibly produced by the growing together of 
two undeveloped tarsal joints. 
The length of the abnormal antenna in this full-grown stage is 
about 6 millimeters. The antenna of a normal imago is about 36 
millimeters. 
Several details in this spontaneous case of homceosis indicated 
that it was a regeneration of the right antenna. For example, the 
thinness of the abnormal antenna in comparison with the stout 
normal antenne—a difference in size which is often found after 
regeneration. The connection between the basal joint and the small 
second joint indicated that the regeneration probably had its origin 
from the basal joint. Here also should be considered the conditions 
under which the Jarva had lived among a lot of more or less mutilated 
comrades with definite cannibalistic inclinations. 
I therefore concluded that the right antenna had at some time been 
bitten off just at the end of the basal joint, or rather a jittle within the 
end of this joint, and that it had thereafter regenerated into the very 
peculiar shape above described. 
Hence it was natural to begin the regeneration experiment with 
amputations in the region of the first and second joint and especially 
in the suture between these joints. I was unfortunately prevented 
from giving the time and attention desired to these experiments, and 
was forced to make the amputations by hand with fine scissors, 
without the aid of a dissecting microscope. By this primitive method 
I could not always make the amputation just where it was intended— 
for example, exactly between two joints; often either a little too much 
or else not quite enough was removed. This condition was of course 
