266 

 Regeneration in Cockroaches. 



BY J. F. ILLIXGWOETH. 



^Yhile eari-ying on life history work with our Hawaiian 

 cockroaches I was interested in noting- the rapid replacement 

 of lost appeiidag-es, etc. Eight of our species have been ob- 

 served. 



Usually, if a leg is broken off Ijcyoud the trochanter, soon 

 after molting, the appendage is renewed at the next molt, wbich 

 occurs in a month or six Aveeks. If the injurv happens shortly 

 before molting the parts are not renewed until the succeeding 

 molt. 



In catching roaches they often lose some parts of the legs 

 and it was ()l)served that these appendages never break off 

 alxwe the trocliautcr. Experiments were tried of cutting off 

 the trochantei' and in some cases the entire leg, next to the 

 body. In each case, where the victim survived, the wound soon 

 scarred over and became heavily chitinized, but regeneration 

 Ap])areutly the renewing cells are located in the proximal 

 segments of the leg. 



The antennae, also, have the power of renewing, even when 

 cut off close to the liead. At the first molt only a few segmenta 

 a])])ear, but if molting continues they are soon of their normal 

 length. 



It is interesting to note that when the tarsi are renewed. 

 they hici< tlie fonrtli segment, in every case observed. This ap- 

 ])arently accounts for many roaches having only four tarsal 

 segments on part of the legs. 



FEBRITAEY ;5ki., lOlC. 



The one hundred twenty-fifth meeting of the Society was 

 held in the usual place, President Illingworth in the chair. 

 Other members ]n-esent : Messrs. Back, Bridwell, Ehrhorn, 

 Giffard, Kuhns, Pemberton, and Swe/.ey and ]\Ir. P. IT. Tim- 

 berlake, visitoi-. 



Minutes of ])revious meeting read and ai»]U'oved. 



Proc. Haw. Ent. Soc. Ill, No. 4, May. 191i 



