266 

 Regeneration in Cockroaches. 



BY J. F. ILLINGWOKTH. 



While carrying on life history woi'k with our Hawaiian 

 cockroaches I was interested in noting the rapid replacement 

 of lost appendages, etc. Eight of onr species have been ob- 

 served. 



Usnally, if a leg is broken off beyond the trochanter, soon 

 after niolting, the aj^pendage is renewed at the next molt, which 

 occurs in a month or six weeks. If the iiijrirv ha]ipens shortly 

 before nujlting the parts are not renewed until the succeeding 

 molt. 



In catching ruaclics ihey often lose some parts of the legs 

 and it was observed that these appendages never break off 

 above the trochanter. Experiments were tried of cutting off 

 the trochanter and in some cases the entire leg, next to the 

 liody. Ill each case, Avhere the victim survived, the wound soon 

 scarred over and became heavily chitinized, l)ut regeneration 

 Apjiarcutly the i-enewing cells are located iu tlie ]U'oximal 

 segments of the leg. 



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

 (•III off close to the head. At the first molt only a few segments 

 ;i]»])('ar, hut if molting coutiuucs they arc soon of their normal 

 length. 



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

 rlicy lack the fourth segment, in every case observed. This ap- 

 parently accounts for many roaches having only four tarsal 

 segments on part of the legs. 



FEBRUAKY 3im., 1916. 



The one hundred twenty-fifth meeting of the Society was 

 lield in the usual place. President Illingworth in the chair. 

 Otiiei' meiubers present: Messrs. Back, Bridwell, Ehrhorn, 

 (liffard, Ivuhns, Penib(M-tou. and Swezev and ^Ir. V. TT. Tim- 

 berlake, visitor. 



]\Iinutes of pi-evious uieetiug read aud a[)]irovc(l. 



Proc. Haw. Ent. Soc. Ill, No. 4, May, 1917. 



