Marmara Clemens

150 PROCEEDINGS ENTOMOLOGICAL SOCIETY ninth abdominal segments while the rest of the insect developed nor- mally, is not without interest. This abnormality is readilj- noted as the sheath (which is composed of the gonapophyses, which are appendages of the eighth and ninth ventral segments) is so reduced that it cannot be seen without magnification of thirty-five diam- eters. TENTHREDELLA SPECIES (PROBABLY VERTICALIS Say) MALE. At Glencarlyn, Virginia, on June 9, 1911, a male of this species was collected, in which the lateral ocelli are entirely wanting. This causes the vertex to be depressed. Along with this abnormality of the head goes a slightly different type of coloration and a narrow- ing of the facial quadrangle, so it is impossible to accurately de- termine this male. The obliteration of the ocelli is the first record of the kind known to me. In this connection, for completeness' sake, it may be well to call attention to the abnormally developed propodium in Oryssits abietes Rohwer, which is described on page 154, Proc. U. S. Nat. Mus., vol. 43, September, 1912. NOTE ON A BARKMINING LEPIDOPTERON OF THE G?ENUS MARMARA CLEMENS. BY AUGUST BUSCK, Bureau of Entomology. In the course of the work on forest Lepidoptera at Falls Church, Virginia, we have lately bred several specimens of Marmara fnl- gidella Clemens, from oak; it is gratifying to find that the biology of the species definitely confirms the generic determination made by Mr. Chas. Ely and myself a year ago, when we transferred the species from the genus Gracilaria to Marmara, solely on pterogos- tic characters. The larva is of the identical flat, deeply segmented form as that of Marmara salictella Clms., the type of the genus. It forms long winding galleries just under the epidermis of young trunks and branches of oak, similar to those of M. salictella Clms. on willow, and leaves the mine in early spring, April, to spin a small cocoon in some convenient crack in the bark. The cocoon is ornamented by similar globular air-bubbles, voided by the larva through the anal opening as is characteristic of the other species of this genus. Imago issued in May. Similar Marmara mines were found less commonly on chestnut, this this but unfortunately the imago were not secured year ; may prove the same species or one of the allied forms, fasciella Chmb., or eloteUa Busck, as yet listed under the genus Gracilaria. OF WASHINGTON, VOLUME XV, 1913 151 Mr. Busck also presented a recent work by Dr. C. Wesenberg Lund of Denmark, 1 which he strongly commended to the members' attention as an excellent biological study. Mr. Busck referred in detail to some of the subjects in the article and passed around the interesting plates of the egg-laying habits of this group of insects. NOTES ON A WOOD-BORING SYRPHID. BY H. S. BARBER, Bureau of Entomology. A hickory log in early stages of decay, which was found in the vicinity of Washington, had lost its bark, and the weather beaten surface of the wood showed numerous holes, with caked damp sawdust that had been thrust out. This work was mis- taken for the borings of the larvae of the Lymexylonid, Meli- tomma sericeum Harris, but when chopped into, the log disclosed numerous short cylindrical grubs of a form that the speaker had never> seen before. These were shown to numerous entomological friends, but no one could place them with any certainty. Speci- mens were caged for breeding and the log was frequently examined for changes in the larvae. At last a pupa was found and this latter disclosed a Syrphid fly (Temnostotna bombylans) the larva of which appears to have been previously unknown. Before this was bred, however, larvae were shown to Mr. A. B. Champlain, who on his return to Harrisburg, Pennsylvania, found similar larva? boring abundantly in very soft rotten willow wood. He also bred the flies, and has forwarded his material to Mr. W. R. Walton. Dr. Boeving and Mr. Shannon also found similar larvae on the Virginia shore opposite Washington. Comparison of the larvae, however, shows great differences in the armature of the spiracles. From this it becomes evident that more than one species is involved in the colonies. Adults bred from these different colonies corroborate this idea, and are more or less different, so that it appears to the speaker that about four species are involved in America under the name Temnostoma bombylans. This name was originally applied to a European form. There are, however, a number of names available for American forms that have been sunk as synonyms of bombylans, but it is not known to what forms these refer. In the first log found, the wood was very hard and brittle but showed signs of ferment, and contained much moisture. The galleries were cylindrical, clean-bored holes, and all boring dust wa- extruded at the surface of the log. Under these conditions the larva? need strong protection against predatory enemies. This is ^iologisheStudien iiber Dytisriden (Footnote: Published in Internation- ale Revue der Gesamten Hydrobiologie und Hydrographie, Leipzig, 1912.).

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