284 
MR. NEWPORT ON THE REPRODUCTION OF LOST PARTS 
series on Lepidopterous insects, the results of which I have now the honour to com- 
municate to the Royal Society. 
Myrlapoda. 
The facts already ascertained respecting the periodical development of new segments 
to the body in this class, led me to anticipate a favourable result in experimenting 
on the reproduction of the antennae and legs. In the spring of 1841, I had placed 
about thirty nearly full-grown individuals of lulls terrestris and lulls niger in a 
closed vessel filled with clay and mould. Many of these individuals deposited ova, 
some of which I succeeded in rearing. 
During the time these Iuli were confined together, I found several of them deprived 
of one of the antennae, and also of some of the legs, which I attributed to their 
attacks on each other. This circumstance led me further to believe that these organs 
when lost are reproduced. In order to put this conclusion to the test, I cut off one 
of the antennae and some of the legs of an individual that had not yet attained to 
more than two-thirds of the adult size of the species, and confined it in company 
with others of the same age. A few weeks afterwards all the specimens had changed 
their skins and grown much larger, having also gained an addition of segments to 
the body ; but the antennae and legs of the mutilated specimen had been so com- 
pletely reproduced, that I could not identify the individual that had been the subject 
of the experiment. As, in consequence of this, the experiment was not entirely satis- 
factory, although it sufficiently proved to me that reproduction had actually taken 
place, I cut off one of the antennae, and some of the legs, from each of three speci- 
mens that had much nearer approached their adult state. These were confined 
together in the same vessel, and were nearly of the same age. After watching them 
closely for about three months, without discovering any signs of regeneration of the 
lost parts, I began to fear that there must have been some error in my previous 
observations. However, I allowed them to remain undisturbed during the whole 
of the spring and commencement of summer, giving them constantly a fresh supply 
of food, the decaying inner bark of trees. 
They continued in this state until the middle of June, when the whole of them 
entered the earth, and each made for itself a little circular cavity, in which it lay 
coiled up in a spiral form, and passed into a state of what has been designated summer 
hybernation, and remained until the end of July. This I found is the usual habit of 
the species, and did not depend on the mutilations, as during the same period I dis- 
covered many Iuli similarly concealed in the earth in their native haunts : many 
individuals die at this period in their estivatories, but these appear to have arrived at 
their full maturity, and become aged, having already deposited their ova in the 
spring. Those which are not yet matured now cast their teguments, and have their lost 
parts reproduced. The casting of the skin is a difficult and tedious occurrence. For 
several days after it has taken place the Iuli are unable to venture forth from their 
