4 Mr. H. J. Carter on the Natural History of the Lac-Insect. 



single straight, sacculated, beaded tube, of the same size through- 

 out, presenting a yellow colour, and giving off the hepatic duct 

 {g) a little nearer one end than the other; while the tracheae 

 \k k) are amassed into bundles, apparently without order, and 

 send forth many of their extremities [m m) through the two small 

 (c c), as well as through the large {b), anal apertures, to terminate 

 on the surface of the lac in the way above mentioned (fig. \dd). 

 Lastly, we come to the ovary {i i i), which consists of a volu- 

 minous tree of tubes apparently branched dichotomously, with 

 each branch, large and small, bearing long elliptical pouches, 

 in each of which, again, is a correspondingly shaped ovum, — the 

 whole nearly filling the body, and terminating in a single ovi- 

 duct {h), which opens (probably through the rectum) at the anal 

 aperture. The ovum (fig. 3), on the other hand, consists of an 

 elliptical transparent envelope {b) filled with little cells (c), each 

 of which contains oil(?)- globules (d) and globules filled with the 

 red colouring matter (e). The oil-globules are spherical, uniform 

 in size, and much larger than the red globules, which are also 

 spherical, but distinctly separated from the oil-globules and 

 from each other. Whether these bodies respectively have deli- 

 cate cell-walls or not, I am ignorant ; but while they are both 

 distinctly defined in the ovum when the insect is first opened 

 under water, both soon burst by imbibition, and become lost to 

 view by dispersion of their contents. Thus the red colouring 

 matter exists originally in the form of distinct globules or in 

 cells in the ovum. 



The further changes in the ovum, preparatory to the full de- 

 velopment of the embryo, I have not followed ; but about the 

 beginning of July the young ones are perfectly formed, and, 

 issuing through the anal aperture in the incrustation, they creep 

 on to the neighbouring parts of the branch, and, soon fixing 

 themselves by inserting their beaks into the bark as before stated, 

 commence secreting the lac or resinous substance, in which they 

 soon become incarcerated. Myriads issue in this way, as may 

 well be conceived when, at a guess, I should think, each insect 

 contained a thousand : but by far the greater number die ; for 

 although the branches become quite red with them, it is only 

 here and there that a few, scattered or in groups, live ; the rest 

 still remain attached to the bark, but dried up and dead, which 

 may arise, perhaps, from not having been sufficiently developed, 

 or not being strong enough at their delivery to pierce the bark 

 for sustenance. 



On leaving the parent, the young Cocctis (PI. I. fig. 4) is of a 

 minium-red colour, about l-40th of an inch long, elliptical, ob- 

 tuse anteriorly, without any division between the head and body, 

 possessing six legs, two antennae, two small eyes, marginal and 



