G. GENERAL NATURAL HISTORY AND ZOOLOGY. 293 



kind of wasp, belonging to the genus PoUstes^ which he had 

 taken and tamed in the Pyrenees during the past summer, 

 and had kept by itself for three months. At first it was rath- 

 er free in the use of its sting, but afterward ate sugar from 

 liis hand, and permitted him to stroke it. 15 A^ August 31, 

 1872,273. 



PROTECTIVE FLUID OF CYMBEX. 



According to Von Rossum, the larva of the genus Cymhex 

 emits a colored fluid with great force through several aper- 

 tures, for the purpose of protecting itself from the attacks of 

 birds and other animals. This substance has been chem- 

 ically investigated, and proves to be mainly an albuminoid 

 compound, having much the reaction of white of egg. The 

 coloring matter is supposed to be chlorophyl, or something 

 similar to it. 5 A, January^ 1873, 110. 



DO FLIES EAT POLLEN? 



The question has sometimes arisen as to whether flies act- 

 ually eat the pollen of plants, or simply carry it away on 

 their legs and backs. Mr. A. W. Bennett, however, reports 

 the result of examinations prosecuted by himself of the stom- 

 achs of various diptera, which were found to contain large 

 quantities of pollen grain, showing that it must have been 

 actually consumed. In reply to the query as to the possibil- 

 ity of insects which are organized for sucking devouring such 

 solid bodies as the pollen grains, it is answered by Milller 

 that the transverse denticulations found in the valves at the 

 end of the proboscis of many diptera are especially adapted 

 for chewing the pollen grains, and for dividing the threads 

 by which these grains are often bound together. 12 A^De- 

 cemJer 19, 1872, 132. 



BENTHAM OX PHYLLOXERA. 



Mr. Bentham, in his anniversary address to the Linnaean 

 Society, in speaking of the grape-vine louse, remarks, as a gen- 

 eral summary of his observations already made, that the 

 Phylloxera, like other aphides, goes through a number of ap- 

 terous generations of a single sex,but multij^lying with enor- 

 mous rapidity; for one or two individuals will lay as many 

 as 500 eggs, fertilizing without previous copulation. It also 



