778 



ZOOLOGICAL SOCIETY BULLETIN. 



TRANSFORMATION OF THE SEVENTEEN-YEAR CICADA. 



From left to right is shown the progressive stages of transformation from the larval stage as it leaves the ground. The figure 



on the extreme left shows the powerful fore-legs of the immature form. 



teen-Year Locust, or properly the Seventeen- 

 Year Cicada, belongs to the Order Hemiptera, 

 or suctorial insects. The species of this Order 

 are not provided with mandibles, but obtain their 

 nourishment by means of a stout proboscis. A 

 familiar member of the order is the common lo- 

 cust or harvest fly, that occurs in this region 

 during the hot weather of July. August and 

 early September, producing a loud buzzing 

 sound as it perches high among the trees. The 

 harsh song of this Cicada — a large ally of the 

 same genus as the one now with us — is the 

 sound that is proverbially alleged to usher in 

 the dog-day weather. The Hemipterous in- 

 sects exist in great variety of 

 forms and habits. Some suck the 

 juices of fruits and others live 

 upon the blood of man and ani- 

 mals. A considerable number of 

 the larger species inflict an ex- 

 tremely painful puncture with the 

 proboscis, ejecting an acid at the 

 same time that causes high inflam- 

 mation. Tile writer has always 

 been cautious in handling speci- 

 mens of the periodical Cicada 

 owing to the apparently powerful 

 beak or proboscis of this species, 

 but he has failed to note an exam- 

 ple make an attempt to inflict in- 

 jury with the organ or at any 

 time to feed. 



DISTRIBTTION OF THE PRESENT 

 SWARM. 



A number of distinct broods of 

 the Seventeen-Year Cicada have 

 been charted by entomologists. A 

 few of these broods overlap in dis- 

 tribution, witli the results that in 

 some states, particularly Pennsyl- 

 vania, swarms of the insects ap- 



LARVAL SHELLS ON AN APPLE 

 BOUGH. 



pear at periods of four or five years apart. New 

 York and the immediate vicinity possesses a 

 single brood, which appears above ground regu- 

 larly every seventeen years. In the records of 

 the United States Department of Agriculture, 

 Division of Entomology, the various broods are 

 known by chart numbers. The present visita- 

 tion is charted as the 1911 recurrence of Brood 

 II. The swarms of this breed occur in a num- 

 ber of counties in the easterly portion of New 

 York as far north as Lake Champlain, on Long 

 Island and Staten Island, throughout the state 

 of New Jersey, eastern Pennsylvania, Mary- 

 land, Virginia and North Carolina. In New 

 Jersey where the Cicadas are ap- 

 pearing in enormous numbers, this 

 insect has been regularly recorded 

 every seventeen years since 1775. 



The Mississippi Valley is now 

 swarming with another important 

 brood of the periodical Cicada, 

 known as Brood III. Its distri- 

 bution is more extensive than the 

 easterly brood, and moreover, this 

 southerly swarm is particularly 

 interesting owing to its being a 

 thirteen-year race. A number of 

 these are charted on the records 

 of the government entomologists. 



OBSERVATIONS NEAR NEW YORK 

 CITY. 



The swarms of the present 

 brood of the Seventeen-Year Ci- 

 cada appeared throughout the va- 

 rious areas in which they were 

 anticipated in perfect fulfillment 

 of the predictions of entomolo- 

 gists. The writer has made a 

 number of observations of the 

 1911 swarms and assisted Mr. 

 William Beutenmiiller, the Curator 



