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Mr Peter Cameron exhibited various specimens of Tenthredinidae, new to the British Fauna, taken by Mr Joseph Chappell in the Manchester district. (1) A new species of Dolerus, distinguished from all the other black and red species by having the abdomen entirely red, otherwise nearly approaching D. lateritius, Klug; (2) Blennocampa micans, Klug; (3) Lyda fulvipennis, Zaddach, a species described in 1863, when only two specimens were known in the Berlin Museum, Mr Chappell's example being thus the third. Mr Cameron also showed Athalia annulata, Fab., taken in England by the Rev. T. A. Marshall. This species was erroneously inserted in our lists, but as we have now this authentic specimen, it may again be included in the British fauna.

PAPERS READ.

1.-On Saricava rugosa, a Bivalve Mollusc; showing an unusual mode of repair. By Mr DAVID ROBERTSON, F.L.S., F.G.S.

It is a common occurrence to see shells which have been repaired by the animal after accidental injuries of various kinds. These repairs, it is well known, are accomplished by a calcareous secretion applied to the points of injury, whether a fracture, a bruise, or displacement of parts, which are often mended even when the fractured edges do not come into proper contact; and in such cases, the shell frequently assumes a more or less contorted appearance. This calcareous secretion is also used by the animal to cover any irritating substance which happens to get inside the valves of the shell; and when this occurs with any of the pearlbearing molluscs, the foreign objects get covered, layer after layer, with nacreous or pearly matter, and in this way pearls are formed. This property is said to be taken advantage of by the Chinese, who place little figures of their gods within the valves of such shells, where they allow them to remain a sufficient time to be coated over with a pearly covering.

Here is an injury to the shell of a mollusc, Saxicava rugosa,—an injury of a different kind,—not accidental, but purposely inflicted by a carnivorous univalve mollusc, which has the power of drilling through the covering of hard shell to reach the animal within, and with much skill, if we may so call it, in selecting the most vulnerable point of attack. It will be seen by the perforations of these boring molluscs, in the numerous examples before us, that they have been done by no random aim, but so directed as to

reach the most vital part of the animal, and at a point from which escape is hopeless. It will also be noticed that the holes are never made on a thick part of the shell if a thinner part affords the same advantage. On this group of Trophons may be seen how the punctures are made in almost every case on the body whorl, and at one particular point, and with scarcely an exception they are on the ventral side, which evidently implies a vantage gained by getting to this part beneath the shell.

On looking at this valve, we find three holes pierced a little apart, near the umbo, and which are covered over on the inner side by a thin layer of calcareous matter. Each patch, it will be noticed, is just a little larger than the hole it covers, and there can be no doubt that these repairs were made by the occupant of the shell. But what I wish to draw attention to is, that although repairs of accidental injuries are common, as before mentioned, yet, with this exception, I have never seen a trace of the least attempt having been made to close up one of these bored holes; they are always open, and it is all the more unlikely that any attempt at resistance could be made, when we consider the character of the shell borers. They appear to pierce the shell with ease, and it is not to be supposed that they have the least difficulty in making their assault without giving either time or opportunity for resistance when they have once pierced the shell.

This singular case of an apparent effort to shut out an invincible enemy cannot be easily accounted for, except by supposing some untoward accident happening to the aggressor or aggressors just at the moment they had pierced the shell and touched the prey, the damage having been repaired afterwards, in the same manner as if caused by accident.

I may further call your attention to a little sand procured from the root of a sponge, kindly sent me by Mr John Kirsop; as also some given by Mr John Young, from the tubes of a beautiful group of annelids, also presented to the Hunterian Museum by Mr Kirsop. Both the annelids and sponge came from Australia; the former from the shores of Kangaroo Island, and the latter from the banks of the river Cygnet, where they had been thrown up by storms and tides, together with many other beautiful specimens of various kinds which were exhibited by Mr Kirsop at our last meeting. Here are also the contents of a little mud from the Bay of Gibraltar, and those of a small parcel from off St Helena,

for which I am indebted to the kindness of Professor Young; and those of another, from my friend Mr Dugald Bell, procured from soundings taken by Captain White off Mocha, in 22 fathoms water, on their way to India; and the contents of another parcel, from Mr D. C. Glen, from the Brazilian coast. In all these cases the quantity of material is small, yet they all reveal the remains of abundant life, which not only represent Microzoa, but the remains of larger forms, as plates and spines of Echinoderms, otolites of fish, spicules of sponges, etc., and give unmistakable proof of the presence of such forms in these localities, and often of the particular species to which they belong. Although in these instances only a small number of species of those that inhabit a particular region may have been secured, yet we may be sure that we have a portion of the prevailing forms which at all times give character to the locality.

In most cases Foraminifera predominate over Ostracoda, and more so in the greater depths of water. But in the sample from the Brazilian coast, sent by Mr Glen, one species of an Ostracod is in great abundance, while scarcely another organism is seen. Such facts come to be of great importance, when the results from different parts of the sea bottom, at the same or different depths, can be compared; and although small gatherings seldom fail to be of interest, and often of much scientific value, it will be understood that larger gatherings will be of more than proportionate value when they can be had.

There has at all times been no lack of voyagers bringing home novelties from distant countries, and often at great trouble to themselves. There are many who, doubtless, would have a pleasure in helping science, were it better known what particular kind of objects or material are wanted. There is generally a tendency in those collecting for others to give most attention to things that please the eye. In a scientific point of view, this is not at all times necessary, as every group of animal life is invested with a history brimful of interest, and the chances of a prize, in most cases, are greater among the obscure forms than among those that are more conspicuous. In regard to material for the microscope, beauty or pleasant appearance does not come into account. It may be the black slimy mud from the sea-shore, or margin of a lagoon, or from the bottom of the sea, attached to the grease of the soundinglead, or brought up on the fluke of an anchor. All of these may

be at times easily procurable, and require no further preservation than to be secured in a parcel or bag, with the indispensable precaution of being accurately labelled with the locality and conditions under which they were found, whether in fresh, brackish, or salt water, and at what depth. Such gatherings seldom fail to be of great interest, and I need not say how proud I am when I happen to be the fortunate recipient.

II.-On a remarkable Lepidopterous Gall from South America.
By Mr PETER CAMERON.

Mr J. M. Campbell has shown me some galls which he found on a thorny plant near Watchman's Cape, Patagonia, and which merit notice. Outwardly, in form and colour, these galls are almost identical with the common oak-gall of Cynips kollari, but are slightly smaller, have no tubercles, but have the outer skin. quite smooth, and, like our species, are formed on the leaf-buds. Internally, however, the structure is very different, there being no spongy mass as in C. kollari, the central cavity being very large, occupying the greater part of the gall, and the outer rim is only about a line thick, while its substance is of a firmer consistency, not spongy as in our species. But the most curious thing in connection with this gall is in the way by which the insect escapes. In the Hymenopterous galls the flies simply eat out a round hole in the side for their passage, and the substance eaten out falls away in fine dust; while the South American species takes out of one side a circular piece of the same diameter as the outer rim, this piece being thinner on the inner than on the outer side, and it remains intact, so that it can be fitted accurately into the hole again. These pieces are not all of the same shape, some being oval, others oblong, while, more or less in all, the outer edge has small indentations. It is further to be noted that the holes are not all in the same position, some being on the side, others in the apex. Internally, the surface is smooth.

Mr Campbell, unfortunately, has only pupae of the maker of these galls, and they prove to be Lepidopterous. Several moths have been reported as gall makers; but the galls which they raise are mere swellings, scarcely comparable to that just described, which is as well formed as those of any of the Cynipidae.

III.-Notes on Clydesdale Hymenoptera. By Mr P. CAMERON. In the following paper I purpose detailing a number of additions to the Clydesdale Hymenoptera, and giving additional localities for species already recorded in the "Fauna and Flora of the West of Scotland," Glasgow, 1876.

TENTHREDINIDAE.

Lophyrus virens, Klug. Rannoch.

Lophyrus rufus, Kl., is possibly Scotch (Oban), as the specimens in Stephen's collection in the British Museum are L. rufus, and not L. pallidus. Mr C. W. Dale, of Glanville's Wooton, tells me that he has Scotch specimens of L. pallidus from the late John Curtis.

Croesus latipes, Vill., perhaps occurs in the district. In September, I found in Clober Wood a larva on birch, that appeared to belong to this species; it was, however, very young.

Nematus longiserra, Thomson.

sallows.

Nematus xanthogaster, Foerster.

Kintail. June.

Larva on

In giving an account of the life history of Nematus crassulus (Proc. Nat. Hist. Soc. Glas., Vol. ii., p. 313), I expressed some doubt as to the identity of that insect with N. xanthogaster, Foer., and N. leucostictus, H. In that doubt I now find I was quite justified. Brischke and Zaddach have figured the larvae (Schr. Phys.-ökon. Ges. zu König. ix.; the letterpress has not yet appeared) of both species, and it is certain that they are distinct from N. crassulus. I am glad to be able to record N. xanthogaster as British, Prof. Zaddach having identified for me an insect taken at Possil Marsh as Foerster's species, it having stood previously in my collection as N. piliserra, Thomson, which name must now sink as a synonym. N. leucostictus is stated to roll down the leaves of Salix aurita. Possibly it is also British, as similar larvae on that plant are not uncommon in Scotland and England. Nematus rumicis, Fall. Houston. August.

Athalia glabricollis, Thoms. Generally distributed. (See antea, p. 129).

Athalia lugens, Kl. Kilsyth; Gleniffer Braes. (Mr Morris Young).

Emphytus tibialis, Kl.
Emphytus serotinus, Kl.

Clober (Mr King). Cadder.

Clober. Imago in September.

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