AUTHOR S ABSTRACT OF THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE, NOVEMBER 18 



THE WAX GLANDS OF THE COCKROACH (BLATTA 



GERMANICA) 



E. H. DUSHAM 



Departmetit of Entomology, Cornell University, 



ELEVEN FIGURES 



INTRODUCTION 



The ability to secrete wax in one form or another is wide- 

 spread among insects, being reported for the Libelluhdae of the 

 Odonata; Notonectidae, Fulgoridae, Cercopidae, Psyllidae, Aphi- 

 didae, Aleyrodidae, and Coccidae of the Hemiptera; Tortricidae 

 and Papihonidae of the Lepidoptera; CoccinelUdae and Cur- 

 cuHonidae of the Coleoptera; and the Tenthredinidae and Apidae 

 of the Hymenoptera. 



That this function should also be found in cockroaches is not 

 surprising, for they are waxy in appearance, feel waxy when 

 handled, and when thrown into water or other fluids float readily 

 as if buoyed up by some oily covering, even after the air has 

 been forced out of the tracheae by pressure. In fact, one of the 

 difficulties encountered in fixing material is to submerge the 

 specimens in fixing fluids, especially when these are used cold. 

 On the other hand, no such difficulty is experienced when hot 

 fluids are used, the hot liquid evidently melting the wax, thus 

 allowing the insects to sink. 



Moreover, it is a well-known fact that the species in question 

 is usually found in warm, damp places, especially in close prox- 

 imity to sweating water pipes, its association with water pipes 

 leading from the Croton Aqueduct in the vicinity of New York 

 City earning for it the popular name of 'Croton bug.' Further- 

 more, references to the literature of this species show that it has 

 been carried for long distances in water mains without drown- 



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