June, 1843.] 279 



depth in the earth, and authorizing the conjecture that Dr. G-. 

 offered, that these infusoria afforded sustenance to the insect during 

 its long absence. He expressed his belief that no satisfactory rea- 

 son had as yet been given for its reappearance at regular periods. 



As another fact, not probably known to the members generally, 

 he mentioned that the yolk of eggs brought from the district of 

 New Jersey at present visited by the insect, had lost, in a great 

 measure, their yellow color. This had been observed in former 

 years, and was supposed by the farmers to be caused by the fowls 

 feeding on the insect. 



Mr. Gliddon stated that in Lycoming county, in this State, 

 whence he had recently returned, the insect had been very nume. 

 rous, but at the time of his visit had nearly disappeared. The sto. 

 machs of some trout which he had caught there were found to be 

 gorged with it. 



Mr. Cassin had been informed that the C. septemclecim was now 

 very abundant in other counties of the State, particularly near 

 Mauch Chunk. He also stated that the irregularity in the time of 

 the appearance of the insect had been supposed to be owing to the 

 overlapping of adjoining districts ; as an example of which Loudon 

 <;ounty, Virginia, was mentioned, where it appears at intervals of 

 eight and nine years alternately. Although, as regards this lo- 

 cality, and perhaps some others, this hypothesis may be correct, it 

 will not apply to all cases. In 1834, the C. septemdecim appeared 

 in the neighborhood of Philadelphia and in the adjoining counties, 

 and again in small quantities in Chester county, in 1836. 



Mr. Cassin expressed the opinion that there are two varieties, of 

 the C. septemdecin, the larger and smaller, both of which appeared 

 in this vicinity in 1834 ; they differ in size, and also in their note. 

 The larger is the one commonly known as the seventeen year 

 locust. 



Dr. Goddard then called the attention of the members to a plan 

 which he had recently adopted for removing a disease, common 

 and very fatal to newly fledged chicks, and familiarly known as 

 " the gapes," and which he considered of importance to be known 

 by agriculturalists. 



Upon opening ihe trachea of a chick laboring under the disease, 

 he discovered there a parasitic worm, which obstructed respiration, 



