54 THE GYPSY MOTH APPENDIX. 



is not quite as large in proportion to the rest of the body. 

 Head black, eyes quite prominent. Antennae black, basal 

 joint stout, projecting about one-third of its length beyond 

 the margin of the head. Second joint four times as long as 

 basal joint, cylindrical, slightly dilated at the outer end. 

 Third and fourth joints about two-thirds as long as second 

 joint. Fourth joint slightly dilated, but not as much as in 

 the preceding stage. 



Thorax entirely black, margined by a distinct white or 

 cream-white line. The color of the thorax and the white 

 margin distinguishes the insect in this stage from the cor- 

 responding stage of P. serieventris. Abdomen of same 

 color and with similar markings as in preceding stage, 

 except that of the four dorsal spots the two middle ones are 

 the largest, the anterior and posterior spots being narrowed 

 transversely. Colors of under surface and legs as in pre- 

 ceding stage. In this stage, as well as those which follow, 

 the insect is almost entirely predaceous. 



Fourth Stage* (Plate 1, Fig. 5.) Length, 7 mm. 

 Head, thorax, wing-pads and scutellum intense pitchy black. 

 Joints of antenna 1 as in third stage ; basal and second joints 

 seal brown, third and fourth joints black. Thorax mar- 

 gined with white, as in preceding stage. Both the marginal 

 and dorsal spots of the abdomen are closely appressed. 

 Across the dark-red ground color of the abdomen fine white 

 transverse lines connect the lateral and dorsal spots. The 

 same variation in color observed in P. serieventris also oc- 

 curs here, and in some specimens the white lines predomi- 

 nate to such an extent as to give the abdomen a light 

 striped appearance. Under surface of body yellowish 

 brown. On the median line near the end of the abdomen 

 are three small, somewhat circular black spots. Femora 

 straw colored, marked longitudinally with brown ; tibiae 

 of same color at junction with femora, shading downward 

 to a dark seal brown. Tarsi dark brown varying to 

 black. 



In this stage the insects feed voraciously. The fourth 

 and last molt, in specimens under observation, took place 

 in about twenty-two days from the preceding molt, but I 



