An Introduction to Entomology: Vol. 3 / or Elements of the Natural History of the Insects

by William Kirby; William Spence

Orthoptera. Mr. MacLeay considers the larvæ of this Order as primarily Thysanuriform[397], though he allows the resemblance between them and Amphipoda to be particularly striking[398]. For my own part, their prototypes appear to me to be in the Crustacea, and their analogical relations to the Thysanura much more distant. I trust this will appear to you the reverse of dubious in a progress through the Crustaceous Orders. I begin with the Isopoda. Take the larva of a Blatta, and place it between a Lepisma, or Machilis, and an Oniscus, or Porcellio; you will find that in shape and width, and the form of its anal styles, it resembles the latter much more than it does the former, with which it possesses scarcely any character in common, except its multiarticulate antennæ. It is remarkable, that amongst the Blattidæ we meet with species that represent both the Oniscidæ and Armadillo or Glomeris[399], the latter being more convex than the former. In their habits the Blattæ certainly agree with Lepisma; and Dumeril, who thought the latter and Podura subject to a metamorphosis, imagined they were related[400].

The Spectres of Stoll (Phasma F.) are so strikingly analogous to another crustaceous tribe, the Læmodipoda, particularly the genus Caprella, that Montagu gave one species the Trivial name of Phasma[401]. The jumping Amphipodiform Crustacea are represented extremely well by Gryllus L., and the Stomapodiform, particularly Squilla Mantis, by Mantis. The resemblance in this last instance is so very striking, that it cannot escape the eye of the least intelligent observer. Orthopterous insects may perhaps one day be discovered analogous to the two other crustaceous orders, the Decapods and Branchiopods; but at present I know of none of that description.

Hemiptera. The larvæ of this order, which in general resemble the perfect insect, except that they have no wings, seem most commonly to belong to the Anopluriform type[402]; but the Aphides, Chermes, and Thrips may, I think, be regarded as more analogous to the genera Podura and Sminthurus in the Thysanura[403]. I have some suspicion that the Nepidæ, Naucoris, and the remipedes, Notonecta, Sigara, &c. may find their prototypes amongst the Crustacea; but my confined knowledge of the latter does not enable me to point to any individual genera or tribes that they may be presumed to represent.

Neuroptera. As the kinds of larvæ of the different tribes composing this order, as it now stands, are very various, it is to be expected that the analogical forms they represent are equally so. The Libellulina MacLeay (whose metamorphosis that gentleman has denominated subsemicomplete, a term warranted by their losing in their perfect state the mask before described[404]) in their oral organs, particularly by their galeate maxilla and distinct ligula[405], have some relation to the Orthoptera, the prototypes of whose larvæ we have found amongst the Crustacea: probably, therefore, those of the tribe in question lurk in that class; a suspicion that receives strong confirmation from the larva of Agrion[406], which in its tapering body and anal natatorious laminæ represents a shrimp. The larvæ of that very peculiar and distinct tribe, the Ephemerina, appear to be intermediate between the Stomapodiform and Thysanuriform types. Their natatory respiratory abdominal laminæ seem copied from the former, and their anal diverging setæ from the latter[407]. The Myrmeleonina, as well in their general form as in their motions and habits, present a most singular analogy with the tribe of spiders, as does also in some respect that of Cicindela. With regard to Panorpa, which Mr. MacLeay remarks is related to Myrmeleon[408], and is a most ferocious insect[409], as its larva has not yet been discovered, nothing certain respecting its analogical form can be asserted; but should it, like the male fly, represent the scorpion, both orders of Arachnida will have their representatives in the class we are considering. The Corydalina, as far as the larva of Hemerobius instructs us, is Chilopodiform, but with a tendency to the Araneidiform Type. The Ametabola also furnish the prototype of the next tribe, the Termitina, which, as is evident both from Psocus and Termes, are perfectly Anopluriform. The Sialina, or Plicipennes of Latreille, excluding Trichoptera Kirby, appear to me to be intermediate between the Chilopodiform and Stomapodiform Types, and not without some relation to the Thysanuriform. Their pediform, jointed, respiratory abdominal appendages, their head and falcate mandibles, seem copied from the first tribe. The same appendages considered as organs of respiration, and their taper forks, are moulded upon the plan of the Stomapodiform Crustacea, and the long seta which terminates the abdomen is upon the Thysanuriform plan[410].

Trichoptera. The larvæ of this order appear also to be constructed upon a double plan. The respiratory threads observable in both the upper and under sides of the abdomen connect it with the Stomapoda, and its cylindrical elongate body with Chilognathiform types in the Lepidoptera[411].

Lepidoptera. The great majority of larvæ in this order are Chilognathiform, but there are exceptions to this remark. Those of the Geometræ recede from this type, both in their motions and the distance and number of their legs. In both these respects they represent the Læmodipoda in the Crustacea[412]. Other caterpillars are Onisciform; and a third sort seem to leave the Annulose type, and imitate that of the Mollusca, and one is figured by Madame Merian[413] which appears to tend even to the Chilopodiform type.

Hymenoptera. In this order the larvæ of the saw-flies, Tenthredo L., are in general Chilognathiform, though some are Onisciform, others Limaciform, and those of Lyda F. (Cephaleia Jur.) and Sirex[414] have a Vermiform tendency, and are a stepping-stone to those of the rest of the order, which are all Vermiform and apods.

Diptera. The majority of this order may be set down as Vermiform, though it is not improbable that some of them bear an analogy to animals that appear far removed from the Annulosa. Thus, the larva of Stratyomis Chameleon seems to exhibit no small resemblance to some of the Polypi vaginati in the Acrita subkingdom of Mr. W. MacLeay[415]. That of Culex and some others is constructed on a quite different type from the rest, and seems to possess some analogy to the Branchiopod Crustacea.

Though some of these analogies are more striking than others, yet in almost all that I have stated there is that kind of resemblance that could not be the result of what is called mere chance; and Mr. MacLeay, by first pointing out this plan of the All-wise Creator, and by laying down the doctrine of analogies in general, as distinguished from affinities in the animal kingdom, has furnished the believer with a new argument against those attacks of the infidel, that would render null those proofs of the wisdom and goodness of the Author of nature with which the animal and vegetable creation furnish us; by affirming most absurdly, and under the most stultifying blindness of mind, that the creatures were in a manner their own creators, their wants under local circumstances stimulating them to efforts that in a long course of years produced all the different forms and organizations that are now to be found in our globe. The affinities and close connexion of beings with each other, so that the ascent from low to high is usually by the most gentle gradations, is the circumstance on which they build this strange and impious theory. But the fact, that certain animals of one tribe were created with a view to certain animals of another, so as to present a striking aspect of correspondence, parallel almost with that of type and antitype, without any real affinity or approximation;—this triumphantly proves a Power above and without them, who has associated them not only in a complex chain of affinities, but has caused them to represent and figure each other, even when evidently far removed, so as to give a mutual correspondence and harmony to the whole, which could be produced only by a Being infinite in power and wisdom, who made all things after a general preconceived plan and system.

iv. We are now to consider the clothing with which larvæ are furnished. Many are quite naked, and smooth or rough only with granular elevations or tubercles orderly arranged; but a very considerable number, especially of the Lepidoptera order, are clothed with hair or bristles of different kinds, in greater or less abundance, and arranged in different modes; and a proportion still smaller have their skin beset with spines or a mixture of spines and hairs. Lyonnet found that the hairs of the caterpillar of the great goat-moth (Cossus ligniperda) were hollow, though not to the apex: probably this is the case with those of other larvæ, as well as with their spines. In this instance they were set, he observes, in a corneous ring, or very short cylinder, elevated a little above the skin. The hair passes through this ring, and appears to be rooted in a soft integument, which clothes the skin within, and upon which the nerves form a reticular tissue, some of which he thinks he has even seen enter the root of the hairs, which perhaps are organs of touch[416].