Part 18

This is a very obscurely marked insect, closely allied to the next species, from which it can only be distinguished with difficulty. Its somewhat smaller size and the two minute white dots on the reniform stigma appear to be the most definite characteristics.

The perfect insect appears in May and June.

Described and figured from specimens in Mr. Fereday's collection.

MELANCHRA VITIOSA, Butl.

(Apamea vitiosa, Butl., Proc. Zool. Soc. Lond., 1877, 384, pl. xlii. 3. Mamestra ochthistis, Meyr., Trans. N. Z. Inst. xix. 20. Mamestra vitiosa, Meyr. Trans. N. Z. Inst., xx. 45.)

(Plate IV., fig. 42; Plate III., fig. 16, larva.)

This is a scarce species in the neighbourhood of Wellington. In Christchurch it is very common.

The expansion of the wings is 1-3/8 inches. In general colouration it closely resembles the preceding insect, but is considerably paler, with the markings much more distinct. There are no clear white dots above or below the reniform stigma, the orbicular is obliquely oval and rather conspicuous, and the claviform is strongly margined with black.

The larva is rather robust, very pale green above with numerous white lines and dots; dark green beneath with yellow dots. In the light part there is a triangle of black spots on each segment. The young larva has a strong pink lateral line, but in mature specimens this line is confined to the anterior and posterior segments only. Length when full grown about 1¼ inches.

This caterpillar feeds on Melicope simplex, and when amongst the foliage of its food-plant it is extremely hard to detect, owing to its protective colouring and sluggish habits. The larva is full grown about October.

The pupa is enclosed in a light cocoon on the surface of the ground.

The perfect insect appears from November till April.

{21}MELANCHRA DIATMETA, Meyr.

(Plate V., fig. 5.)

This species has occurred at Wellington.

The expansion of the wings is 1-3/8 inches. The fore-wings are reddish-brown; there is a short longitudinal black streak near the base, an obscure yellow transverse line at about one-fourth, and several short oblique brown or yellow marks on the costa; the orbicular is oval oblique outlined very distinctly in yellow; the reniform is white, margined with yellow towards the base of the wing; there is a black longitudinal streak at the base on the dorsum, which bends upwards at about one-fourth, and runs in a somewhat curved direction to a little above the tornus. The veins are faintly marked in black, and there are several large yellow dots between the veins near the termen; the termen itself is slightly indented, the cilia are reddish-brown. The hind-wings are greyish-brown with the cilia reddish. There are two very conspicuous curved yellowish stripes on each side of the thorax.

The perfect insect appears in September and October. It is a rare species.

MELANCHRA TARTAREA, Butl.

(Graphiphora tartarea, Butl., Proc. Zool. Soc. Lond., 1877, 384, pl. xlii. 2. Mamestra tartarea, Meyr., Trans. N. Z. Inst. xix. 21.)

(Plate V., fig. 6.)

This species has occurred on the Murimutu Plains in the North Island. In the South Island it is a common species in the neighbourhood of Christchurch.

The expansion of the wings is 1½ inches. The fore-wings are dark chocolate-brown; there is a short, dark-margined, pale transverse line near the base, and another at about one-third, the claviform spot is small, oval, dark brown, margined with black, the orbicular and reniform are very large, pale brown and very conspicuous; there is a broad pale brown terminal band, and a narrow shading of pale brown along the dorsum. The hind-wings are dark grey and the cilia dull white.

This species can easily be recognised by the pale terminal band of the fore-wings.

The perfect insect appears in March and April.

MELANCHRA HOMOSCIA, Meyr.

(Mamestra homoscia, Meyr., Trans. N. Z. Inst. xix. 21.)

(Plate V., fig. 7; Plate III., fig. 10, larva.)|.

This dull-looking species has hitherto only occurred in the Wellington district, where it seems to be fairly common.