46 Transactions. — Zoology. 



Female of second stage red, darkening with age ; elongated ; 

 segmented: average length Jin., but some specimens observed 

 exceeded -J-in. : occupying a groove in a mass of white, or 

 greyish, or yellowish wax, which leaves the dorsal region 

 usually exposed ; this waxy mass would doubtless be more or 

 less globular if it were not squeezed nearly flat by pressure 

 between the laminae of the tree-bark, the consequence of the 

 pressure being that the wax spreads out round the insect, 

 sometimes with a diameter of more than an inch. Antennae 

 atrophied, reduced to a single small joint bearing several short 

 hairs. Feet entirely absent. Kostrum large ; mentum conical, 

 trimerous. The anal tube seems to be simple. Epidermis 

 covered with great numbers of circular compound spinnerets, 

 which are most numerous near the margins. 



Larva red, elongated, somewhat slender, active : length 

 about -^-^vn. Antennae of seven joints, the first and last the 

 longest, second and sixth shorter and equal, the rest still 

 shorter and equal ; the third, fourth, and fifth are also the 

 narrowest, so that the antenna is rather irregular. Feet mo- 

 derate : tarsus longer than the tibia ; there are no tarsal 

 digitules, the lower pair being fine hairs. Anal tubercles very 

 small, setiferous. Mentum trimerous. 



Male unknown. 



The adult female of this species is sometimes "partheno- 

 genetic," as will be noticed presently. 



Hah. In New Zealand. The second stage of the female is 

 found between the layers of bark on Podocarpus totara, in the 

 Eeefton district. My specimens are from Mr. Eaithby. 



I have included this insect in the genus Coslostoma, on 

 account of the absence of the rostrum and mentum in the 

 adult stage, and other generally normal characters ; but it 

 departs from the type in the ten-jointed antenna of the adult, 

 and the seven-jointed antenna of the larva. Both of these 

 antennae, also, are abnormal in not being conical or tapering 

 from base to tip in the adult, and as far as the penultimate 

 joint in the larva. These points serve readily to distinguish 

 the species, apart from the crushed condition of the waxy mass 

 in the second stage, which indeed may be only accidental. 



I have stated that this insect is " parthenogenetic." Whe- 

 ther there is really any such thing as true parthenogenesis 

 amongst insects is a question which I need not discuss. Mr. 

 Buckton (Monogr. of British Aphides, vol. i., p. 61) remarks 

 that there are " interesting forms in which we might almost 

 believe, though the evidence be but negative, that no male 

 occurs ; " and he goes on to say that Leuckart and von Siebold 

 " distinctly assert that such anomalies exist in nature." At 

 the same time, other observers consider that there are among 



