صور الصفحة
PDF
النشر الإلكتروني

kept up. I have now examined seven artificially flattened crania ot Chinook and other flat-headed Indians, and in all of them the sagittal and coronal sutures are in a great measure obliterated. The lambdoidal suture is not so frequently affected. The lateral lines of sutures (the spheno-frontal, spheno-parietal, and squamous) not being subjected to the pressure, are but little altered."*

My own observations of the state of the sutures in skulls distorted by artificial means are quite in agreement with those here quoted. But though bandaging does cause obliteration of the sutures concurrently with the annular deformations which immediately result from it, it does not appear to have been the cause of either the one or the other in the dolichocephalous skulls from the Long Barrows. Since the publication, ten years ago, of Dr. Gosse's work “On Artificial Deformations of the Skull,” there has been too much disposi. tion to attribute every peculiarity of cranial form to that cause. I have myself, on different occasions, and up to a somewhat recent period, fallen into this error. Minor degrees of saddle-formed contraction in the coronal and temporal regions, are not only to be observed in the ancient British crania, which are more particularly considered in this paper, but likewise in those of Negroes and in many other races, especially such as are naturally dolichocephalous.

After much consideration and inquiry, the conclusion I have come to is that this contraction is altogether normal, and connected with the natural form and course of development of the brain. It corresponds almost precisely with the situation of the great fissure of Rolando, which divides the anterior from the middle cerebral lobes ; and just in proportion as these neighbouring lobes may tend to assume a full and rounded form, so must be the amount of the corresponding intervening depression which is communicated to the surface of the skull. In like manner, other depressions which are observed on the cranial surface may represent the interspaces between other lobes of the brain ; as that between the temporal and the posterior and the upper surface of the cerebellum. Such, I think, is the explanation of certain depressions on several ancient Gaulish skulls, from the cavern of Orrouy (Oise), which are preserved in the Museum of the Society of Anthropology of Paris, and of which casts, through the liberality of M. P. Broca, have been presented to several collections in this country.

* Cranial Deformities, &c. Nat. Hist. Review, 1864, p. 106.

XXIII.- DESCRIPTION OF AN OVO-VIVIPAROUS MOTH, BELONGING

TO THE GENUS Tinea. By A. W. Scott, Esq., M.A.*

I am induced, from the novelty of the subject, to lay before the Society a short description, accompanied by illustrations, of a Moth recently found on Ash Island, which possesses the remarkable, and, I believe, unique quality of being ovo-viviparous ; a quality hitherto known to exist only in some few groups of the Insecta, but never attributed to any species of the Lepidoptera. Those admirable writers, Kirby and Spence, in the 3rd Volume of their “ Introduction to Entomology,” page 63, express themselves thus, “ By far the larger portion of Insects is oviparous in the ordinary acceptance of the term. The Ovo-viviparous tribes at present known are scorpions; the flesh-fly, and several other flies; a minute gnat belonging to Latreille's family of Tibulariæ ; some species of Coccus ; some bugs (Geocorise, Lat.), and most Aphides, which last also exhibit the singular fact of individuals of the same species being some oviparous, and others, ovo-viviparous ; the former being longer in proportion than the latter.” You will perceive that no mention is made by these scientific gentlemen in 1828, the date of the work from which I have quoted, of any Lepidopterous insect possessing the faculty of ejecting living larvæ; and I cannot find, on careful reference to many subsequent publications, some of recent date, any notice to the effect that this peculiar function appertains to any species of butterfly or moth. I, therefore, take the liberty to submit this singular fact for your consideration and future investigation, trusting that such information, however small in itself, but tending, nevertheless, towards the perfecting of that branch of Natural History, to which this Society exclusively devotes itself, will be received by the members with some degree of interest.

As my fimily takes an equal part with myself in all matters connected with Natural History, I will, with your permission, use the pronoun, we, as I now proceed to describe more accurately and at greater length the economy of this curious little creature.

· * Reprinted from the “Transactions of the Entomological Society of New South Wales, vol. I., part I., Sydney, 1863. This paper is of much interest, as record. ing a fact hitherto unique among the Lepidoptera, and one to which the attention of Entomologists for confirmation of Mr. Scott's observations should be directed. Ep.

The Lepidopterous insect brought under your consideration is closely allied to the genus “ Tineaof modern authors, is of small size, and boasts of no outward singularity of form, nor extraordinary beauty of colouring to distinguish it from others of that group. It was after dark, in the early part of the month of October, 1861, that we first captured a specimen with the hand, being attracted at the moment by its elegant colouring, and wishing to secure it for the cabinet. Fearful that the plumage might be injured by the struggles of the Moth, while endeavouring to escape, it was gently compressed, and on opening the hand we observed numbers of minute, but perfect larvæ, being ejected from the abdomen in rapid succession, and moving about with considerable celerity, evidently in search of suitable shelter and food. This incident, so singular and new to us, required further confirmation, and consequently many more of a similar kind (of course all females) were caught and attached to corks previously covered with black paper, and subjected to the closest scrutiny. These Moths shortly commenced to deposit their living progeny with rapidity, the small white fleshy larvæ being seen with great distinctness on the black surface of the paper ; thus affording clear and satisfactory proof that this Insect, the only one of its order at present known, is unquestionably ovoviviparous, and will represent in future this peculiarity among the Lepidoptera ; similar to those few species existing in the Hemipter. ous and Dipterous orders. This fact having been ascertained, our attention was incited to the care of the little strangers, and to procure suitable shelter and food for them, in the hope that we should be able to rear them, and thus to supply a correct account of all their metamorphoses. In this we were guided by the form of the perfect insect, and accordingly placed before them grains of maize, pieces of flannel and woollen cloth, shreds of partially decayed paper, some fungus and lichen, and other materials known to be the food of caterpillars belonging to the genus Tinea and neighbouring genera. Unfortunately, they turned with distaste from all these supplies, with the exception of the cloth and flannel, and even to these they attached themselves with reluctance. We, however, persevered and put them in a dark and roomy box, aware of the marked dislike to light of larvæ possessing depredatory habits, and left them undisturbed for a week; at the end of which we were pleased to find that small silken tunnels or tubes had been constructed on the surface of the brown cloth, and that the denuded

appearance of several places exhibited signs of their ravages. From this cloth they shortly afterwards transferred themselves to the flannel, where they fabricated small portable cases, composed of two separate pieces, of an irregular oval form, joined at the sides, but leaving apertures at each end, and being thus comfortably housed, we entertained sanguine hopes of rearing them. These hopes, however, were not to be realized, for towards the end of November (nearly two months from their birth) they ceased to thrive, and eventually all perished.

[ocr errors][ocr errors][ocr errors][ocr errors][merged small][merged small][merged small]

The larva (Fig. 1., natural size; Fig. 2., magnified), attained to the length of 2} lines, but this manifestly is under its full growth ; the head large, somewhat depressed, and with the first segment of the thorax slightly corneous, and of a brownish colour, the rest of the body softly cylindrical and almost colourless, possessing a lateral row of small brownish points, emitting delicate hairs ; sixteen feet, the thoracic ones being large compared with the others.

The imago ? (Fig. 3) measures in expanse of wings, nine lines, the fore wings are elongate, somewhat lanceolate, with the costal margins arched. A broad transverse, rather oblique, glossy brown bar, bifurcate towards the costal margin, occupies the centre and a triangular patch of the same colour the tips ; the remaining

portion, or ground colour, being silvery white. The inferior wings are pale brown glossed over with a golden tint; a deep marginal fringe surrounds all the wings. Head tufted in front with white; thorax brownish, having a white spot on the centre of the collar; abdomen and legs pale shining brown.

The under surface of the insect, pale golden brown, clouded with darker on the superior wings.

The male unknown to us. Wings deflexed in repose.

Maxillæ ..... Very small, almost rudimentary.
Maxillary palpi (Figs. 4 and 4) distinct, separated, composed

apparently of several joints, and bending down
in front of the mouth, which they almost con-

ceal; partly clothed with scales. Labial palpi. . . (Figs. 5, 5, and 6, divested of hair) large

divergent, porrected forwards and slightly upwards ; 3-jointed, the middle joint being the longest, the whole covered with scales

and with a few setæ on the 2nd joint. Antennæ . .... (Fig. 7) long, filiform, scaly. Legs . . . . . . . Differ greatly in size, the tibiæ and tarsi of

anterior pairs (Fig. 8) being only about equal in length to the tarsi of the 2nd pairs (Fig. 9), which again bear the same relative proportion to the posterior pairs (Fig. 10), which are large and powerful. 2nd pair with two, and posterior with four large spurs, at apex of tibiæ, which is covered with longish hairs. Tarsi 5-jointed, slender, scaly.

We have retained in this instance the generic name of Tinea, as our Moth agrees in all its characteristics with that genus, with the exception of the labial palpi being larger than usual, and that our insect is ovo-viviparous. As we failed in affording proper nourishment to the larvæ, we think it probable that they exist in their natural state upon decaying animal or vegetable matter, as found to be the case with the Sarcophaga carnaria (or common Blow-fly), and some others, which produce their young in a living state.

« السابقةمتابعة »