Sept., 1903.] BuENo : Life-History of Pelocoris Fkmorata. KID 



Ponte du Dxtiscus inaririiia/is et queU[ues autres Insectes aciuati(iues," 

 read December 9, 1874, before the Societe Entomologique de France, 

 describes the act in Ilyocoris cimicoides, in connection with the same 

 function in Notonecta glaiua. His description follows : 



"These insects {^Ilyocoris ciniicoides and jYotonerfa glauca) attach themselves 

 firmly by means of their anterior and intermediate pedes to the stems of plants, hold- 

 ing the head high in the same way as Dytiscus, making peculiar motions with the 

 swimming legs ; the rostrum is sunk deeply into the plant for support, and an incision 

 is made with the ovipositor. The motion of this apparatus, which is more compli- 

 cated than that o{ Dytiscus, can scarcely be properly examined, as little can be gath- 

 ered from the outside ; it can be guessed at from the abdominal movements from front 

 to back and from back to front. The incision calls for about one minute's labor on 

 the part of these insects ; it is not ver}' deep, only about 2 or 3 mm. long, and the 

 ovum is only about three fourths of its length enclosed by it, being set obliquely, so 

 that one of its ends is nearly quite out. It should be noted that the free portion cor- 

 responds to the cephalic extremity of the embryo." 



It may be assumed, in default of direct obser\ation on Pelocoris, 

 that the mechanism of oviposition is substantially as described, and it 

 is to be hoped that some observer may be so fortunate as to be able to 

 describe the process in detail. However, as regards the attachment of 

 the ovum, Pelocoris femorata seems to differ from Ilyocoris cimicoides, 

 as far as my observation has gone. Out of about 100 ova examined 

 by me, some found in natural conditions, others deposited in aijuaria, 

 none has been met buried in the plant tissue to any extent. The ma- 

 jority have been found attached axially to the stems or leaves of Cerato- 

 phyllum, and secured to them by a glue in which the ovum is set and 

 which surrounds the slender stem or leaf to a variable extent. The 

 adhesion is not very firm, however, and the ova are readily detached. - 



As development advances, the eyes begin to show at the micro- 

 pylar extremity of the ovum as two little red lines which grow plainer 

 day by day. The embryonic stage lasts from 22 to 27 days, the 

 greater number (over two thirds of the ova I bred) emerging on the 

 twenty-fourth day. 



First Nvmph.-vl Ixstar. 



Immediately after emerging from the ovum, the nymph is transpar- 

 ent, white and colorless, except that each abdominal segment has a 

 broad dark luteous band at the connexivum. Also, the eyes are red 

 and well-marked. The tarsal claws of the second and third pairs of 

 pedes are dark and noticeable. The single claws of the first i)air are 

 colorless and transparent. The short rostrum is transparent pale lute- 



