274 Fiftieth Report ox the State Museum 



stories of all kinds concerning it and its ways find ready credence among 

 the people. Each return is also of interest to scientists as it gives, for a 

 brief time, an opportunity for studying the ways of this singular insect. 

 It is only by carefully observing their number as they appear from time 

 to time, that an approximate idea can be obtained of the rate at which 

 the insect is diminishing in number with its successive returns. Thanks 

 to the studies of the late Dr. Riley, we know pretty closely the distribu- 

 tion of the different broods of the insect in this country and are able to 

 foretell their appearance. The advent of the Hudson river valley brood 

 in i8g4 is of special interest to us, because it is the widest in range and 

 the most numerous of any of the six or seven broods known to occur in 

 the State of New York. 



Characteristics of the Insect. 

 Most people have seen a Cicada (commonly known as a locust) and many 

 have seen both pupseand adults of the "periodical Cicada." The wing- 

 less, red-eyed pupa will be readily recognized with the aid of figure 2 of 

 plate IX, and needs no further description. The perfect insect may easily 

 be distinguished from the common dog-day Cicada or harvest-fly. Cicada 

 tibicen, by the eyes and the veins of the wings being a bright red. More or 

 less of the ventral surface of the abdomen (especially in the male) and the 

 legs are of a dull red. 'i'he dorsal surface of the body is almost entirely 

 black. If we compare the periodical Cicada with the dog-day Cicada or 

 harvest-fly, we will find that the latter is a considerably stouter insect with 

 green markings on the thorax, greenish eyes, and the veins of the wings 

 bright green, while the ventral surface is more or less covered with a 

 white powdery substance. 'J'he male and female of the periodical Cicada 

 with their wings expanded, and one with its wings closed as in rest, are 

 represented in figure i of plate IX. 



Oviposition. 



The female, when ready for oviposition, selects a small branch, prefer- 

 ably of oak or apple, but almost any tree except the pines, and placing 

 herself near its tip she proceeds to deposit her eggs. With her ovi- 

 positor she saws a series of oblique holes in the twig with splintered 

 outer edges, as represented in figure 5. In each she places from 

 ten to twenty eggs, in pairs side by side, but separated from each other 

 by portions of woody fibre, and inserted somewhat obliquely so that 

 their ends point upward. A fissure is made and filled with eggs in from 

 fifteen to forty minutes, when at a slight distance on the twig the opera- 

 tion is repeated. 



