occasionally scobinate, protruberance, or it may bear a pair 

 of such protruberances which have been termed The 

 Octavals (Oporinia, pi. xxv.) (Seitz. Macro-lepidoptera of 

 the World, iv. p. 51). 



CERATA AND MAPPA. Pierce. 



In the Acidaliince the eighth sternite consists of a 

 chitinous plate which is internal for about half its length 

 and then coming to the surface is continued in two pointed 

 arms, which I name The Cerata (Acidalia, pi. xxi.). These 

 show almost constant asymmetry, the right being com- 

 monly larger and more fully developed than the left. In 

 the natural position the cerata lie in the lateral grooves of 

 the body and in most cases project beyond its anal 

 extremity. 



Covering the cerata is a loose semi-circular flap, 

 clothed with long narrow scales. This flap I term The 

 Mappa. 



ABDOMINAL PLATE. White. 

 In the Eupitheciince there is a plate, similar to that 

 which bears the cerata, to which attention was drawn by 

 Dr. Buchanan White, who figured it in a certain number 

 of species in the " Entomologist," Vol xxiv., p. 129, 1891. 

 Dr. Petersen has also figured the abdominal plate in his 

 " Eupithecia," but as I read the preparations rather 

 differently, I have added figures of this organ (Eupithecia, 

 pi. xxvii.). A similar sternite plate is found in Cato- 

 gramma, a Central American Nymphalid, in Pero, a South 

 American Geometrid, in the Pyralidce, and probably also 

 in other groups. Under natural conditions the genitalia 

 are withdrawn beneath this plate. 



THE SEVENTH SEGMENT. 

 This is sometimes highly developed, being produced 

 on either side as an extensile pouch or bag clothed with 

 hairs, and bearing a spiracle. These bags are The Coremata 



