THE STATE ENTOMOLOGIST. 



105 



its varied stages ; b, b, b representing the larvae of three different 

 [Fig. 47]. growths and sizes. In the an- 



nexed Figure 47, J, 5, represents 

 the full grown larvae of the bo- 

 gus Colorado Potato-beetle. It 

 will be seen at once that the 

 head of the former is black, that 

 the first joint behind the head is 

 pale and edged with black be- 

 hind only, that there is a double 

 row of black spots along the side of the body, and that the legs are 

 black, the ground-color of the body being of a Venetian-red. In the 

 other larva (Fig. 47 b), on the contrary, the head is of a pale color, 

 the first j lint behind the head reddish-brown and edged all round 

 with black; there is but a single row of black spots along the side of 

 the body and the legs are pale, while the ground color of the body is 

 of a pale cream, tinged with pink or flesh color. Such are the distin- 

 guishing characteristics of the two larvae; but itis an interesting fact 

 that these characters are not always constant. Thus the individuals 

 of the second (last summer's) brood of 10-lineata larvae which fed 

 on the horse-nettle in my garden were all of them much paler than 

 were those of the first, potato feeding brood, from which they had de- 

 scended; and furthermore the lower row of spots was very indistinct 

 and in many entirely obsolete, while the head, instead of being black 

 was entirely brown. Whether this variation from the normal type 

 was due to the food-plant or not, I shall not at present offer an opin- 

 ion, but I should have been doubtful about the species had I not bred 

 the perfect beetle (10-lineata) from them. Again as I shall immedi- 

 ately show the young larva of juncta similates in its markings the ma- 

 ture larva of lC-lineata. 



The eggs of 10-lineata (Fig. 46, a, a) are of a translucent orange- 

 red color, while those of juncta (Fig. 47, a, a) are whitish, with a faint 

 tinge of flesh-color, and still more translucent. The newly hatched 

 larvae of the former are of a dark Venetian-red, and they become 

 lighter as they grow older, while the newly hatched larvae of the lat- 

 ter have the body as light as the full grown individuals. Singularly 

 enough, however, the newly hatched larvae of juncta instead of having 

 the light yellow head and the single row of spots of the mature in- 

 dividuals, have a brown head and two rows of spots, the lower being 

 less distinct than the upper row, and placed exactly in the same posi- 

 tion as the lower row on the mature larvae of 10-lineata (see Fig. 46 b, 

 lower figure]. 



I subjoin a more full description of Doryphora juncta. That of the larva of Doryphora 10- 

 lineata will be found in Dr. Fitch's N. Y. Reports, Vol. Ill, pp. 231-2. According to Dr. Fitch, 

 the ground color of this last larva is "pale-yellow" in the mature state ; according to Dr. Shimer, 

 in his excellent article on the preparatory stages of this insect, it is "orange." In the immature 

 •larvse it is almost always of a dull Venetian-red, though in the mature larvae the color becomes 



