478 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



The Egg-sac (Plate I, Fig. 4). — As tlie body of the female begins 

 to swell from the eggs forming inside, tlie beginning of the egg-sac is 

 made. The female lies flat on the bark, the edges of the body turned 

 slightly upwards, and the waxy material of which the sac is composed 

 begins to issue from countless pores on the under side of the body, but 

 more especially along the sides below. As the secretion advances the 

 body is raised, the cephalic end being still attached, until, near the 

 completion of the sac, the insect is apparently standing on its head, 

 nearly at right angles to the surface to which it is attached. The egg- 

 laying commences as soon as a thin layer of the secretion has formed 

 on the nnder side of the abdomen, and it continues during the forma- 

 tion of the sac. There soon appears around the edge of the abdomen 

 a narrow ring of white feltlike wax, which is divided into a number 

 of flutings (Plate I, Fig. 3). These flutings grow in length and the 

 mass of eggs and wax under them increases, forcing the female up- 

 ward until the sac is completed. When completed, it is from two to 

 two and one-half times the length of the female's body. It is of a 

 snow-white color, and the outside is covered with 15 of these longi- 

 tudinal ridges or flutings, of subequal size, except that the middle one 

 is smaller than the others. The upper part of the sac is firm in text- 

 ure, but the lower is looser and thinner, and from the middle of the 

 under side the young make their escape soon after hatching. The 

 size of the sac and the length of time required in its growth depends, 

 leaving the weather and the health of the food-plant ont of consider- 

 ation, upon the number of eggs which the female deposits. _ So long 

 as oviposition continues, the secretion of wax accompanies it andthe 

 egg-mass grows. Concerning the rate of growth Mr. Coquillet gives 

 the following instance: 



" On the 4th of May of the present season I marked a large number 

 of females which were located upon the trunk of an orange tree that 

 was not in a very healthy condition. These females had just begun 

 to secrete the cottony matter, the latter at this date being in the form 

 of short but broad tufts around the margin of the abdomen, those at 

 the hind end of the latter being longest. By the 31st of May tlie 

 cottony matter was equal in length to one-third of the female's body, 

 and by the middle of July it about equaled in length the entire body 

 of the female. As the egg-masses of some of the females upon the 

 same tree were longer by one-half than the bodies of the females which 

 produced them, it is very probable that at least another month must 

 elapse before the egg-masses of the females which I observed would 

 be completed. It is altogether likely, however, that these egg-masses 

 would have been completed in a shorter time had the females been 

 located upon a healthy tree. The egg-masses found upon healthy 

 trees attain larger size than those found upon sickly trees, owing 

 doubtless to the fact that the females living upon trees of the former 

 kind are more vigorous than those upon unhealthy trees." 



The male Lakva — probable second Stage. — Neither Mr. Co- 

 quillett nor Mr. Koebele were able to distinguish the male larvre until 

 these had reached the stage in which they form their cocoons. Among 

 the specimens studied at the Department, and which were sent alive 

 from Los Angeles by Mr. Koebele, we have found a larval form 

 which has not yet been described, aiid which we strongly suspect 

 may be the male in the second stage. This form is illustrated at Fig. 

 7, Plate II. It difliers from our supposed second stage of the female 

 in its more slender form, longer and stouter legs, and longer and 

 stouter antennse. The legs and antennse are not only relatively 



