The bites of these insects appear to distress some people much more than others, probably owing to constitutional differences. I should mention that the females alone engage in these attacks, the males being quite harmless and subsisting entirely on honey, which is doubtless the natural food of both sexes. The male and female mosquito are readily distinguished, the specimen figured belonging to the latter sex; her companion is chiefly remarkable for his plumed antennæ and beautiful palpi, which are very long and gracefully plumed. As many of the harmless insects which will be investigated are often mistaken for this species, and destroyed accordingly, I should like to advise my readers that they may at once distinguish all the venomous species of gnats by their long, lancet-like proboscis and loud humming noise during flight. Closely allied to this insect is _Culex argyropus_, which might be called the coast mosquito as it is always found near the seashore, its larva living in brackish pools just above high-water mark. The perfect insect may be also seen skating along the surface of the water like a {43}gerris[6]; it may be at once distinguished by its dark colour,. Family TIPULIDÆ. _Corethra antarctica_, n.s.[7] (Plate IV., fig. 3, 3a larva, 3b pupa). An elegant little gnat, frequenting the margins of ponds and ditches during the spring months. The larva (Fig. 3a) is bright green, ornamented with numerous yellow spots; it is very sluggish, living in the green slime weed which floats on the water in such large masses during that season. Not being very common it is difficult to find, as its colour so closely resembles that of the weed which it always frequents. The pupa (Fig 3b), is not very agile, and is nearly always observed suspended from the surface by its thoracic air-tubes and caudal fins, the abdomen being directed upwards and thus bringing the two pairs of organs close together. In its metamorphosis and general appearance this insect forms a convenient link between the present family and the Culicidæ. Family TIPULIDÆ. _Chironomus zealandicus_, n.s. (Plate IV., fig. 2, 2a larva, 2b pupa).