93 



their origin as possible, while the insects were in the act of feeding. 

 A block of wood containing the set» was (;ut from the tree and sec- 

 tioned with the microtome (Plate I). The accompanying photo- 

 micrograph illustration shows a section thus prepared with the beak 

 and seta?, inserted. The beak, in this case, was taken from a male 

 feeding on the Carolina poplar. Many sections have been made, and 

 show no appreciable points of difference from the one illustrated. It 

 will be noted in the illustration that the sheath penetrated somewhat 

 into the bark, but is not pushed into the harder wood. In all speci- 

 mens examined, this seems to be true, the beak being pushed only 

 slightly into the outer bark, while the seta? are thrust to variable 

 depths into the cells of the plant. 



Despite this evidence as to the fact that the adult cicadas feed, 

 which in the case of almost smy other insect would have been convinc- 

 ing, doubt has recently been expressed as to whether it could be con- 

 sidered true that the cicada feeds in the sense of taking nourishment. 

 The use of the mouth parts as above illustrated was considered to be 

 the result more of hereditary instinct than anything else, and, while 

 it was admitted that the beak might be thrust into the tissues, this 

 was considered to be simply a sampling or tasting of the juices of the 

 plant on the part of the insect. At various times, but particularly 

 rather late in the evening, both sexes of cicadas have been taken from 

 trees in the act of feeding, and quickly opened, so as to expose the 

 stomach, or so-called crop, and this has been found in many instances 

 to be distended several times its usual size with the sap taken from 

 the trees. 



According to Marlatt (1. c.) the alimentary tract of the male is con- 

 sidered to be rudimentary, and no food is taken by this sex. As 

 shown in the foregoing, males have been observed manv times in the 

 act of feeding, and the photograph to which attention has been called 

 shows the seta? of a male in the tissues of the plant. Males, as well 

 as females, have been taken in the act of feeding, and their stomachs 

 found distended with sap. Furthermore, dissections of the alimen- 

 tary tract of the male shows that it is not rudimentary, l)ut apparently 

 normally developed for this group of insects. The intestine, while 

 small, is continuous to the anus, and is reasonabl}^ large for insects 

 subsisting on liquid food. The esophagus and salivary glands are 

 well developed, while the stomach and crop is rather large and capa- 

 ble of considerable distention. 



The setse are long and tubular and much coiled with the intestine, 

 all being more or less bound togeth.er with tracheal threads, so that 

 dissection is rendered somewhat difficult. On the whole the alimen- 

 tary canal of the male seems to be as fully developed as that of the 

 female. It may be mentioned as a point of importance in this con- 

 nection that both sexes void quantities of fluid excrement from the 



