524 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1914. 
(C) In 1840 Saage(4) received from one of his pupils a male Prionus 
corarus Fabr., with an abnormal thorax. The mesothorax was 
unchitinized and instead of the elytra carried a pair of fully developed 
legs, pointing upward and backward and inserted in the exact place 
where the elytra normally are attached. The metathorax carried 
normal wings (ale). The abdomen was no more chitinized than is 
usual on the upper side under the wings. When the insect attempted 
to fly, it moved the upwardly pointed legs simultaneously with the 
wings. It was otherwise normal except that it lacked the scutellum, 
and that the prothorax carried only two spines. 
(D) In 1887 N. M. Richardson (5) reared a male Zygzna filipendulae 
which had five wings but only five legs. The specimen was collected 
as pupa together with about 700 others in the neighborhood of Cam- 
bridge. The posterior left leg was apparently entirely absent and its 
place was occupied by a fifth wing which was much smaller than the 
normal hindwings, slightly folded, and differing in color, but in no 
wise misshapen. ‘The wing was supposed to have been immovable 
in the live insect. Bateson(1) and Sharp both examined this speci- 
men but could not reach a definite conclusion as to the exact point 
of the attachment of the extra wing, because they were not permitted 
to injure the insect by removing the wing or the thick hair covering 
around its base. Sharp was inclined to believe that the wing was 
attached along the length of the posterior coxa and described the 
specimen, on this basis, as an abnormality, which carried a reduced 
wing instead of a normal leg on its posterior coxa; but he noted that 
a careful examination might give quite a different result. Bateson 
reproduced two drawings by Richardson which show the specimen 
from the underside and the enlarged wing. 
Besides these four cases of homeeosis in insects, Bateson described 
a series of cases in Crustacea, but it would carry me too far to discuss 
these interesting cases or the numerous others since recorded. I 
shall make an exception, however, of the experimental work by 
Herbst, which I will here briefly mention. 
Herbst(6), who sought to ascertain the réle which utility plays in 
the regeneration, asked himself the following questions: Do the eyes 
of these Crustacea regenerate? and if so, would they also do so in 
darkness where these organs would serve no purpose and where their 
regeneration would consequently be superfluous? His results, 
reached through experimentation, were briefly as follows: 
If one of the stalked eyes of a Paleemon, Palinurus, Sicyonia and 
others. is removed, it regenerates as an eye. If, on the other hand, 
the stalk is removed together with the eye, an antenna-like organ 
will in some cases be regenerated. This very peculiar difference in 
the regeneration proved to be due to the fact that the ganglion 
opticum in these Crustacea is located in the eye stalk and hence was 
