The Zoologist/3rd series, vol 1 (1877)/Issue 11/Proceedings of Scientific Societies
PROCEEDINGS OF SCIENTIFIC SOCIETIES.
Entomological Society of London.
October 3, 1877.—Prof. Westwood, M.A., F.L.S., President, in the chair.
Donations to the Library were announced, and thanks voted to the donors.
Mr. W.L. Distant exhibited a specimen of the ravages of Dermestes vulpinus (Fab.) in a cargo of dried hides from China. On the arrival of the hides in this country they were found to be infested and gnawed into holes by swarms of the insect in their different stages, causing a damage of from fifteen to twenty per cent, on the value of the cargo. It is not unusual to see this well-known insect amongst these articles, but quite unprecedented to find it in such numbers and causing such an amount of damage. In fact, its appearance had quite paralyzed the importation of the hides, and gave further proof of the value of Economic Entomology in the arts and manufactures.
Mr. M'Lachlan exhibited a portion of a wooden case containing hides from Shanghai, which was riddled with borings of the larvæ of this beetle.
Prof. Westwood remarked that some years ago the attention of the Society was drawn to the depredations of this beetle in a cargo of cork.
Prof. Westwood exhibited drawings of the pupa of a trichopterous insect (Anabolia nervosa), which swam about in water like a Notonecta, but used its middle legs as swimming apparatus. Prof. Westwood also made remarks upon the structure and situation of the mouth organs of the pupEe of Trichoptera, and stated that the mandibles of the pupae were unlike those of the larva, while these organs were quite aborted in the imago. The Professor suggested that the mandibles of the pupa were for the purpose of enabling the insect to eat its way out of the case in which it had undergone its transformation, and in which, after cementing down the mouth, it was obliged to turn itself completely round, so as to escape at the opposite free extremity.
Mr. M'Lachlan confirmed this view of the function of the mandibles of the pupæ.
The President next exhibited a small lepidopterous insect from Lake Nyassa, apparently a species of Psyche, which had been sent in a paper packet with a pupa-case of a Tachina, from which it was stated that the moth had been produced. Prof. Westwood was inclined to believe that the larva of the moth might have simply made use of the empty pupa-case to undergo its transformation in.
Prof. Westwood read a post-card from Mr. Albert Müller announcing the formation of an entomological station at Basle.
The President then referred to the lepidopterous larva attached to a specimen of the homopterous Eurybrachys spinosa, which had been handed over to him by Mr. Wood-Mason at the last meeting, and exhibited drawings of both insects, the former being evidently identical with the species formerly described as being parasitic upon Fulgora candelaria (Trans. Ent. Soc. 1876, p. 519). In the absence of direct observation, the President was inclined to believe that the relation of the lepidopterous larva to the Homopteron was one of true parasitism, the former insect feeding on the waxy secretion of the latter, it being well known that certain lepidopterous larvae of the genus Galleria feed upon wax.
Mr. Wood-Mason stated that the interesting specimen which he had handed to Prof. Westwood at the last meeting consisted of a lepidopterous larva clinging by its anal pair of prolegs to the free extremity of a stout, tough, flaccid cord, which was firmly fastened to the dorsal surface of the abdomen of the Homopteron. The specimens were captured in August or September, 1870, at Bangalore, South Lidia, by Mr. G. Nevill. The caterpillar was closely allied to Epipyrops (West.). The cord to which it was clinging, Mr. Mason considered to be the wet and matted remains of a case or sac, from the imperfectly closed aboral or free end of which the caterpillar had suddenly withdrawn itself (the case-bearers, as well known, readily being able to turn in their cases) on immersion in alcohol, and on which its anal pair of prolegs had closed in their death-grasp. The end of the cord fastened firmly to the back of the Homopteron being the oral or attached end of that case; i.e., the end by which the case-bearers fasten themselves when at rest to the twigs and branches of the plants on which they live, the attachment being quite as firm, or even firmer, than that of the present specimens. Mr. Wood-Mason's view of the nature of the relation of the caterpillar to the Homopteron in all these cases had always been that the former is the messmate of the latter rather than its parasite, merely making use of it as a vehicle whereon to reach its vegetable food, just as in the curious case recently brought to notice by Fritz Müller ('Nature,' vol. xv., p. 264), and employing,—as Colonel Godwin-Austen's valuable note on the specimen found by him on Aphæna, sp., and his own examination of that specimen in its cocoon seemed conclusively to prove—some of its messmate's wax to cover its body (and in some instances for the construction of a case), in order probably to render itself less conspicuous to its enemies (Ichneumonidæ, Tachinidæ, &c.) than it would be as a naked, fleshy, yellowish grub upon the white wax-covered surface of its messmate's body. He had opened the flattened squarish cocoon constructed by Col. Austen's specimen, and found the body of the enclosed caterpillar still clothed thickly on its upper surface with the satiny asbestos-like waxy substance secreted by its messmate. This specimen was probably identical with Professor Westwood's Epipyrops, while the one from Bangalore represented a different but closelyallied form, distinguished in the larval condition by the presence of a well developed case, which may or may not have been rendered less conspicuous by a covering of wax borrowed from its homopterous "chum."
With reference to the firmness of the attachment of the cord to the back of the Homopteron, Mr. Jenner Weir reminded the Society that the larvæ of Psyche were always most firmly fixed, and Mr. M'Lachlan stated that the larvæ of Phryganea glued down their cases with great firmness under water.
Mr. W.L. Distant raised the question as to whether the Homopteron frequented the plants on which the caterpillar fed or whether the latter was omnivorous.
Prof. Westwood also mentioned a small dingy moth from Brazil, of which numbers had been found upon the Three-fingered Sloth, Bradypus tridactylus.
Mr. Meldola exhibited a collection of Lepidoptera, from Ceylon and the Nicobar Islands, formed by him in 1875. Among them were a few species new to science. The collection had recently been worked out by Mr. F. Moore.
Mr. H. Goss exhibited a series of specimens of Lycæna (Cupido) Avion, taken in the Cotswolds in June, 1877. One-third of the specimens exhibited were far below the average size, the remainder being of the normal size. Both forms were taken flying together at the same time of the year and in the same locality. Mr. Goss stated that according to his experience these dwarf specimens did not occur in the same proportion in other parts of the country where the species was taken. The specimens he had obtained in Devonshire and Northamptonshire were, as a rule, of the average size.
The Secretary stated that the Longicorn beetle exhibited at the last meeting, which had been sent from Birkenhead by Mr. David Henderson, had been identified by Mr. C.O. Waterhouse as Monohammus titillatus (Fab.), a species inhabiting the United States.
Papers read.
"On Notiothauma Reedi, a remarkable new Genus and Species of Neuroptera from Chili, pertaining to the Family Panorpidæ" by R. M'Lachlan, F.R.S., &c.
"On the Lepidoptera of the Family Lithosiidæ in the Collection of the British Museum," by Arthur G. Butler, F.L.S., F.Z.S., &c.— R. Meldola, Hon. Sec.