New Zealand Entomology/Hemiptera
The present Order of insects, although of very limited extent, contains several important species, of which the noisy Cicadas, destructive Aphides, and numerous Bugs, and Lice, can be cited as familiar examples. The Hemiptera may be conveniently divided into the two following groups:—
The Homoptera, comprising all the species in which the anterior wings are entirely membranous, and—
The Heteroptera, including those having the basal portion of the anterior wings thickened, and quite opaque.
These peculiarities have induced some entomologists, who regard the structure of the wings of the greatest importance in classifying, to arrange the insects included in the Homoptera and Heteroptera, into two distinct Orders; but their uniform character in all other respects renders this, I think, hardly desirable.
This beautiful insect may be found in great numbersamongst brushwood during the hot sunny days so common from January till March. Its larva inhabits the earth earlier in the summer, and its curious pupa can often be observed crawling up the stems of trees in order to allow the perfect insect to emerge. After this has taken place the exuviæ still remain firmly attached to the tree, and are very conspicuous objects; but if it is desired to remove them great care must be taken not to break off the legs, which are always very brittle.
The perfect insects are at once betrayed by their loud singing, which, in certain localities, becomes quite deafening. This noise is entirely confined to the males, and proceeds from two large drum-like organs, situated on the under surface of the abdomen near its base, which, in conjunction with the curious ovipositor existing in the females constitute good sexual distinctions throughout the family. The structure of these two organs having been admirably described by several European authors renders it quite unnecessary for me to do so here.
Closely allied to the present insect is Cicada muta, the female of which is depicted on Plate XX., fig. 2. The male is often of a reddish-brown colour, but the insect is an extremely variable one. It is found in similar situations to C. cingulata, but appears rather earlier in the year.
Cicada iolanthe, n.s. (Plate XX., fig. 3, 3a larva, 3b pupa).
This is the first species of Cicada to appear in the spring, and is found during November and December. Its larva (Fig. 3a) is a curious little animal, the two hind-legs being very long. I am at present unable to state with certainty what constitutes its food, but am extremely doubtful whether it consists of the juices imbibed from the roots of plants, as is generally supposed. The anterior legs, although probably chiefly constructed for digging,appear to be also suited for raptorial purposes, which leads me to believe that the insect may be carnivorous in its habits. The pupa (Fig. 3b) does not materially differ from that of the last, except in size, and its empty exuvia is also frequently found attached to the stems of trees.
The perfect insect may be at once discovered by the peculiarly shrill note emitted by the male.
This family is extensively represented in New Zealand, but as I have not yet been able to obtain any information respecting their specific identity I am compelled to pass them by for the present, hoping that future investigation will reveal much that is interesting in their habits, and also help both gardener and agriculturist to protect himself from their ravages.
Coelostoma zealandicum (Plate XX., fig. 4 ♂).
This species is figured as a representative of this very curious family chiefly on account of its great similarity to a Dipterous insect, the rudimentary condition of its posterior wings being most perplexing to the beginner. Its habits have been amply described by Mr. Maskell, in his work on the Coccididæ of New Zealand, to which I consequently refer.
Corixa zealandica, n.s. (Plate XX., fig. 5).
Abundant throughout the summer in all slow-running streams. The larva closely resembles the imago except that it has no wings. Its food probably consists of the juices of other insects. The present insect invariably swims withits back exposed, thus differing considerably from the English Water-boatman (Notonecta glauca), whose keel-like back is kept beneath the water, while the two long hind-legs are rapidly moved backwards and forwards like oars.
Cermatulus nasalis (Plate XX., fig. 6, 6a larva).
This insect may be beaten out of various trees during the summer, and is usually taken in some abundance in February amongst white rata blossoms, on which it may be often observed sucking the honey from the blossoms with its long rostrum. Its larva, which is represented at Fig. 6a, is found in similar situations.
This concludes the series of insects I have selected as representative of the several orders in New Zealand. The brief sketch of entomology thus given is of necessity extremely fragmentary, and many important groups and families are entirely unrepresented. Should, however, this little book induce some of its readers to investigate insects for themselves, I shall feel that my efforts have been amply rewarded.
- This genus is frequently called Melampsalta.