Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 52. (Budapest 1960)

Móczár, L.: The loess wall of Tihany and the nesting of Odynerus spiricornis Spin. (Hymenoptera, Eumenidae)

brought by the wasp from the shore of the Balaton in one minute, during the constructing phases of an average 5 minutes. It excavates generally 5 mud pills with the help of its water supply, in an average of 23". The pills are pasted to the turret in 10". It presses the pill to the rim of the turret by its head, holding the mud back by its posterior legs from the outside. The several mud pills are put side by side in only one-third of the cases, they are generally deposited at a distance of one pill from, or oppositely to, each other ; thus they will desiccate more rapidly. The wasp does not always enlarge the deepest lying portions of the turret. It daubs or fortifies the walls of the passage or the inside of the turret also by scraped-out pills. One of the wasps constructed a 63 mm long burrow (of which the turret was 30 mm) in six hours and forty minutes. Having finished with the forming of the cell, the wasp deposits its egg by coming out of the burrow and retreating backwards into it, and only then does it provision the future larve. Contrary to literature data, it stores the nest by (an average 7) sawfly larvae of mainly Neurotoma nemoralis L. and partly N

. flaviventris Retz. and not by those of Lyda inanita. The wasp seals up the cells, then also the entrance of the burrow itself by a small mud stopper. The materials excavated during the construction of fresh cells are being used by the wasps for the additional building of the turrets, the leveling of the burrow or the further stabilization of the turrets, but they will also frequently throw the pills out. One cell is dug out in 2 hours. In the hottest period and for 2—3 times per day, the wasp departs for an average 62 minutes, in all probability to feed during these intervals in its work. Further experiments are needed to find out the periodical changes of the two stages of the larvae found in the same nest : those of a fresh, greyish-white, shining skin, and the dull, yellow, strongly curved ones with some loss of its water content. The length of the period needed for this change would namely decide whether they could have descended form identical parents or, as one might reason from some phenomena and the few data at our disposal, also the Odynerus species will intrude into alien nests to build their fresh cells there. Should this be demonstrated, we may have found a further link in the evolution of these insects, living in aggregates, toward their social habits. References : 1. A n d r é, E. : Species des Hyménoptères d'Europe et d'Algérie (Beaune, 1886, 2, Vespides, p. 405—917, Pl. XXVI—XLVI). — 2. Chrétien, P. : Nouvelles observations sur les Hyménoptères ravisseurs de Chenilles (Bull. Soc. ent. France, 6, 1896, p. 410— 412).— 3. E n s 1 i n, E. : Die Tentredinoidea Mitteleuropas (Beihefte d. Dtsch. Eut. Ztschr., 1912—1917, 1918, p. 1—790). — 4. F r i e s e, H. : Die Bienen, Wespen, Grab- und Goldwespen (In Schröder : Die Insekten Mitteleuropas insbes. Deutschlands, 1, 1926, p. 1—192). — 5. G i r a u d, J. : Hyménoptères recuillis aux environs de Suse, en Piémont et dans le département des Hautes-Alpes, en France (Verh. zool.-bot. Ges. Wien, 13, 1863, p. 11—46). —6. Móczár, L. : Beobactungen über den Nestbau einiger Odynerus-Arten (Zool. Anz., 125, 1939, p. 70—80). •— 7. Móczár, L. : Az Odynerus spiricornis Spin, tevékenysége (Allait. Közlem., 47, 1960, p. 119—123). — 8. N i e 1 s e n, E. T. : Moeurs des Bembex (Spolia Zool. Mus. Hauniensis, 7, 1945, p. 1—174). — 9. R e y, P. : Sur le comportement d'Odynerus spinipes L. (Hym.) au cours de la construction de son nid (Bull. Soc. entom. France, 51, 1946, p. 116—118). — 10. R o 11 e r, H. : Faunistisch-ökologische Studien an der Südosthänge des Bisamberges (Zeitschr. f. Morph, u. Ökol. d. Tiere, 31, 1936, p. 295—327). — 11. Ver ho e ff, C. : Beiträge zur Biologie der Hymenoptera (Zool. Jb. Syst., 6, 1892, p. 680—754).