10 Bulletin Wisconsin Natural History Society. [Vol. 9, Nos. 1-2. 



Odonata, the abdominal transverse stripes of bees, wasps, Syrphid 

 flies, etc.. 



A final comparison of the wing movement of Odonata, bees and 

 butterflies, shows remarkable parallel development. In general 

 insects possess both vertical and horizontal wing movement; the 

 latter being absent in the three types named, and likewise in some 

 moths. These types fold their wings with tip to tip, not in roof 

 fashion over their abdomen, with the under wing covered by the fore 

 wing. As a result, the hind wing is considerably stronger, the venation 

 is well developed and transverse supports strong; while in the other 

 types the horizontal folding of the hind wing under the fore wing 

 necessitates an elongate development of venation with slight trans- 

 verse supports. When more specially compared, we find that bees and 

 butterflies move all four wings simultaneously, while dragonflies move 

 their wings alternately, the main stress being laid on the hind wings. 

 We may therefore say, vertical wing movement increases speed of 

 flight, while the addition of horizontal movement tends to decrease 

 the speed. 



The lecture was illustrated by about fifty colored lantern slides 

 and diagrams. 



Dr. Dernehl reported that there was now a sufficient amount in 

 the treasury to enable the committee to secure more popular lectures 

 for the general meetings. The matter was discussed by Messrs. 

 Colles, Barth, Dernehl, Graenicher, Burrill and Russell. 



Upon motion the meeting then adjourned. 



Milwaukee, February 9, 1911. 



Meeting of the combined sections. 



President Barth in the chair. 21 people present. 



Mr. A. C. Burrill as secretary pro tem. 



Minutes of the last section meeting read and approved. 



Mr. E. E. Teller read a paper on The Type Fossils From the 

 Paleozoic Formations of Wisconsin. A full abstract of Mr. Teller's 

 paper will be found elsewhere in this volume. 



President Barth then announced that the meetings of Wisconsin 

 Academy of Science and allied scientific societies would take place in 

 Madison next week on the 16th and lt7h. Suggestions for closer 

 affiliation of the Academy with the local societies were invited. 



Dr. B. E. W. Sommer then read a paper on Animal Poisons. Science 

 has demonstrated that the popular view that poisons are derived 



