864 Pomona College Journal op Entomology 



there are many photographs from sjjider webs. These were obtained only after 

 I)atient experiment. 



This work shouhl go far towards making tliis rather neglected group 

 of animals better known. 



A PROBLEM IN THE FLIGHT OP INSECTS 



HERBERT OSBORN 



Ann. Ent. Soc. Am. Vol. V, 1912. 

 One of the prevalent tlight movements among the slender winged species, 

 is the backward motion taken by so many of them in tiying. The hawkmoth 

 in its approach and retreat to flowers, takes a most decided backward move- 

 ment, the backward flight of a honey bee, in its initial tlight from the hive, 

 when it is fixing the location of the entrance of the hive, is also one of the 

 best examples of this mode of flight. The explanation of this movement is 

 accounted for on the basis of an adaptation in the wing for a forward and 

 backward movement. The angle of the wing is so placed with reference to 

 the axis of the body, that it represents different degrees ranging from a right 

 angle to one of 35 to 45 degrees. "The direction of force of each wing would 

 form an angle to the median axis of the body, and that at a point where these 

 would neutralize each other, the effect would be to produce a stationary con- 

 dition of the insect whereby it would hover at a fixed point, and that a slight 

 further rotation forward would serve to i)ush the insect in a backward direc- 

 tion." JI. Moles. 



MIiMANOMMA SPECTRUM, EIN NEUER DORYLINENGAST DES 

 EXTRE.MSTEN MIMIKRY TYPUS 



E. WASSMAN 



Zool. Auz. Hd. XXXIX, 1912. 

 Among the guests of the driver ant Dorylus (anomma) nigricans 111. 

 subsp. spostedti, there were found in two different migrations a most peculiar 

 form. It appeared like an ant to some degree, but proved to be a beetle of 

 the family Stapliylinida\ This remarkable form was given a new genus 

 MinKiiioiiiiiiii, witii the specific name of spectrum. 



W. H. 



A I'HOTECTIVE ADAPTATION IN A BRAZILIAN MEMBRACID 



WM. M. MANN 



Psyche, Vol. XIX, Oct., 1912. 



The author tells of ('. h(ski (ierm. which has a very large pronotum. The 



specimens he first attem|)ted to capture flew away, leaving the large pronotum 



behind. He believes that this structure is distinctly an advantage to the 



animal, its use being coiiiparable to the loosely jointed tails of certain lizards. 



W. H. 



