76 Transactions. 



black, the brown areas get very dark, while the reticulations show up white 

 and sharp, and the larva can be plainly distinguished within the egg. In 

 most cases the brown equatorial belt is broken by a small arm of light yellow 

 joining the top and bottom yellow areas, and sometimes the brown micro- 

 pylar area extends one or more arms of brown joining it to the equatorial 

 belt. Infertile eggs remain a creamy tint, and quickly collapse. 



Note. — Laid in crevices in large uneven batches of sixty eggs or more. 

 Well attached to object, but slightly, if at all, to each other. Batches of 

 sixty and seventy-eight eggs obtained. 115 and 302 eggs obtained from 

 one moth. Laid in November. Period of incubation, eleven days. The 

 larva emerges through the top of the egg to one side of the micropyle, and 

 makes its first meal off the empty shell, sometimes giving its neighbours 

 a help too. 



(Described, 17th November, 1912.) 



Bityla defigurata Walk. 



Xylina defigurata Walk., Cat. Lep. Brit. Mus., 33, Supp., p. 756. Bityla 

 thoracica, ib., p. 869 ; Butl., Cat. Lep. N.Z., p. 10. B. defigurata 

 Meyr., Trans. N.Z. Inst., 19, p. 31 ; Fereday, List N.Z. Lep., 

 Trans. N.Z. Inst., 30, p. 335 ; Hudson. N.Z. Moths and Butter- 

 flies, p. 29, pi. 5, fig. 33. 



Fairly common. Can be taken in great numbers at " sugar." 



Class. — Upright. 



Shape. — Spherical ; sides much bulged ; top slightly flattened. Many 

 eggs, owing to pressure from their neighbours while still soft, are somewhat 

 forced out of their true circular form. 



Dimensions. — Diameter, 0-61 mm. ; height, 0-51 mm. 



Sculpture. — Strong corrugations or ribs radiate from the micropylar 

 area to the equator, converging below. About one in two of the ribs coalesce 

 with another midway between the equator and the micropyle. There 

 are from thirty-three to thirty-six ribs in all, about seventeen of which 

 reach the micropylar area. Between the ribs finer equidistant reticulations 

 apparently form quadrilateral cells, but examined with a high power it is 

 found that they are really modified hexagons with strong longitudinal sides. 

 These transverse reticulations are about 0-02 mm. apart. The longitudinal 

 ribs are about 0-04 mm. apart at the equator. 



Micropyle. — Situated in a rosette of twelve elongated cells, which is 

 surrounded by a band of hexagonal cells, longer than broad, lengthened 

 in a direction radial from the micropyle, very irregular in size, and about 

 sixteen to eighteen in number. The micropyle is depressed crater-like 

 within the rosette, which is raised slightly. Diameter of micropyle, 

 0-005 mm. ; diameter of rosette, 0-06 mm. ; length of hexagonal cells sur- 

 rounding the rosette, 0-03 mm. ; width, about 0-02 mm. 



Shell. — Strong ; transparent ; shiny ; very slightly roughened within 

 cells when viewed with a high power. 



Colour. — When fresh laid, pale creamy-white. In a few days a light- 

 brown ring appears on the upper surface of the egg just above the equator, 

 and an irregular area of light brown covers the micropylar cap. The light 

 brown intensifies to a beautiful rich russet-brown, and at the same time 

 encroaches more upon the egg. The greater part of the brown area at the 



