15 



often reaching a length of one or two inches, and giving a hoary appear- 

 ance to certain spots on the trunk. Clinging to every hair is a glittering 

 drop of honey dew. The bundle of waxen bristles is in fact a contriv- 

 ance admirably adapted to remove the copious flow of saccharine excre- 

 ment which would otherwise condense about the insect and exclude 

 communication with the outer air. 



Mr. Pergande has made many slide mounts of the coccid, and his 

 preparations, cleared with potash, show that the long anal thread is 

 produced by an internal chitinous tube, formed by the union around 

 the end of the anal canal of numerous spinnerets. These are the chiti- 

 nous terminations or formative tubes of major wax glands, which open 

 into the intestine in two encircling ranks, one above the other. The 

 union of these spinneret tubes forms a rigid chitinous honey-dew organ, 

 which is capable of a forward and back motion and can be protruded a 

 considerable distance out of the body. When withdrawn, the opening 

 is closed by several ranks of stout converging spines. This internal 

 organ is in truth the ninth abdominal segment. The eight preceding 

 segments of the abdomen are marked by a pair of spiracles on either 

 side of each. The spiracles have large and simple openings, but within 

 the body form trumpet-shaped tubes, in the constricted necks of which 

 are seen large pores, the openings of lubricating wax glands. The 

 existence of one or of two rings of these spiraeular pores is the most 

 marked distinction between the sac-like females before and after the 

 second molt. There are no spiracles anterior to the abdominal portion 

 of the body in the female, nor are any other organs visible upon the 

 exterior save the elevation of the clypeus, with its single-jointed lower 

 lip, or clasper, from which issue the mouth bristles. The internal frame- 

 work of the buccal organs is large and similar in appearance to that 

 seen in the Diaspinae and the Lecaninse. It does not appear to possess 

 the sucking apparatus of the former group, and is probably as simple 

 in structure as in the Lecanmse. The eye spots seen under the skin in 

 living specimens disappear in cleared specimens and have no external 

 cornea. The sac-like females, when they have reached full size and have 

 cast off their mouth bristles, undergo still another metamorphosis, in 

 which they regain legs and antennae, but lose all the organs of nutri- 

 tion. The female in this ultimate stage has a well-segmented body, 

 rouDded behind and sparsely clothed with hairs. The antennae are long 

 and nine-jointed; the legs are large and strong and of the normal adult 

 type. There is no trace of mouth parts or of anal tube. The adult is 

 thus an ordinary monophlebid. It is capable of locomotion and does 

 occasionally wander about. But ordinarily it is unable to leave its cell 

 in the bark, and does not entirely free itself from the skin of the pre- 

 ceding stage, but merely ruptures the inclosing sac, shoves off the 

 pygidial cap with its accumulations of wax, and presents the end of its 

 body at the crevice in the bark for the reception of the male. After 

 fecundation eggs are deposited and are collected beneath the body of 



