666 SUMMARY OF CURRENT RESEARCHES RELATING TO 



similar cases. The larvae, which are able to destroy their host iu a few 

 days, were hatched by Hesse and identified by E. Grirschner as those of 

 Lucilia splendida Zett. and Meig. 



Ravages of Exotic Fruit-fly near Paris.* — A. Giard noted in 

 1900 the occurrence of an exotic fly, Ceratites capitata Wied., near Paris. 

 Since then, no precautions having been taken, the insect has continued 

 its insidious work, and in some localities has been seriously affecting the 

 peach crop. 



Habits of Tsetse-Flies.f — F. Creighton Wellman has studied Glos- 

 sina palpalis wellmani Austen in the Esupua " fly-belt." The district 

 contains various antelopes, but human blood forms the greater part of 

 the tsetse-fly's food. The flies hide in the tall grasses and sedges near 

 the river, also on stones, trunks of trees, vines, and bushes. When a 

 native appears the flies follow him. Some were seen in the " desert " bush 

 away from the river. The fly bites most viciously during the heat of 

 the day, less readily in the evening and early morning. 



Cause of " Markflecke." — J. C. NielsenJ has made a zoological study 

 of the " Markflecke " — linear or semilunar spots seen on the annual 

 rings of wood in birch, hazel, and other trees. He finds that they are 

 due to the larvae of a fly Agromyza carbonaria Zett. whose life-history 

 he has been able to work out. 



Habits and Structure of Gall-midge. § — M. Leitner gives an 

 account of Resseliella pkm, a new Cecidomyid. The time of flight and 

 oviposition coincides with the fructification of the fir. The eggs are 

 laid between the still fleshy tender seed-scales, the larvae burrow into 

 the soft ovule, upon whose contents they are nourished. The larva 

 leaves the seed either before the winter or in the following spring, and 

 lives upon the ground. The complete cycle of development occupies 

 two years, an adaptation related to the fertilisation of the fir which 

 occurs every second year. A description of the larva, pupa, and imago 

 stages is given. 



Antennal Sense Organs in Diptera.|| — E. Rohler describes in 

 Volucella bombylans on the club-bke segment of the antenna a double 

 pit. In other species three pits occur. From analogy he concludes 

 these organs possess an olfactory function. There are pale hairs on the 

 same segment with a like function. In general it appears that all the 

 antennary sense organs are similar in Brachyceraa. 



Dragon-flies in Brackish Water.^f — Raymond C. Osborn has experi- 

 mented on the extent to which dragon-fly nymphs can endure brackish 

 water. In ponds in which nymphs were found the average density was 

 about 1 • 0008 at a temperature of 72° Fahr. Sea-water has an average 

 density of 1*026. Nymphs of Lestes unguiculatus and other forms were 



* Comptes Rendus, cxliii. (1906) pp. 353-4. 

 t Ann. Nat. Hist., xviii. (1906) pp. 242-4. 

 % Zool. Jahrb., xxiii. (1906) pp. 725-38 (1 pi.). 

 § Verh. k.k. Zool. Bot. Ges. Wien, lvi. (1906) pp. 174 86 (5 figs.). 

 || Zool. Anzeig., xxx. (1906) pp. 211-19 (6 figs.). 

 ^ Amer. Nat., xl. (1906) pp. 395-9. 



