6 



BULLETIN 



U. S. DEPARTMENT OF AGRICULTURE. 



When first deposited, eggs that have been kept under observation 

 were of a cream color. Later they became salmon color and just 

 before hatching the crimson markings of the inclosed nymphs were 

 visible through the shell, a somewhat triangular area on the head be- 

 ing especially conspicuous. 



NYMPH STAGES. 



There is a marked variation in the coloration of different nymphs 

 in the same period of growth and individuals vary considerably in 

 coloration from day to day. The writer has observed a marked differ- 

 ence in coloration of different 



Fig. 8.— Southern green plant-bug: Egg-cluster, viewed 

 from above. Enlarged about 6 diameters. 



individuals after the third and 

 fourth molts, as indicated by 

 Morrill (7) in his figures of 

 nymphs in the fifth ins tar. 

 There are found in the fourth 

 and fifth instars both light and 

 dark nymphs, as well as others 

 of intermediate coloration. In 

 the case of numerous individ- 

 uals that have been under ob- 

 servation it has been found 

 that in the fourth instar the per- 

 centage of nymphs of the light 

 and dark types— if such they may be called — is about the same. 

 Nymphs in the fifth instar belong for the most part to the light type. 

 In the following descriptions the color notes should not be con- 

 sidered as having too great significance. Up to and including the 

 third instar these notes refer, in so far as coloration is concerned, to 

 normal or average nymphs, during the summer months. For the 

 nymphs in the fourth and fifth instars two forms are 

 described. One represents the darkest and the other 

 the lightest form that the writer has found. 



While the writer has not had the opportunity of 

 examining the nymph stages of Nezara liilaris, the 

 species with which viridula is most likely to be con- 

 fused in the United States, it is evident from Whit- 

 marsh's (13) descriptions and figures, especially with 

 regard to the coloration and markings on the dorsal 

 surface of the adbomen, that the nymphs of liilaris 

 and viridula are quite distinct. In viridula the num- 

 ber and arrangement of the light-colored spots on 

 the dorsal surface of the abdomen of nymphs in the second to fifth 

 instars, inclusive, are very constant (although some of them are not 

 apparent in the fifth instar, as they are covered by the wing pads), and 

 serve to distinguish the nymphs from those of liilaris, in which these 

 spots are not present. (Figs. 10 and 11.) 



Fig. 9.— Egg of South- 

 ern green plant-bug, 

 lateral view, show- 

 ing embryo within. 

 Highly magnified. 



