488 JOURNAL OF ECONOMIC ENTOMOLOGY (Vol. 10 



These two instances would show that fly larvae such as Sarccq)haga, 

 or other omnivorous larvae, find no difficulty in entering the chrys- 

 alis under the wing covers during the first few days of the chrysalis 

 stage and before the wing covers begin to fit tightly around the edges. 



There seems to be a peculiar odor to the chrysalids that attracts 

 flies, and a dead chrysalis proves to be a still greater attraction. Dead 

 chrysalids that happened to be left in uncovered jars and were after- 

 wards examined and dissected were in many cases found to contain 

 large numbers of larvae of the small flies of the PhoridoB family, and 

 the adult flies could be noticed flying around the jars in large numbers 

 after dead chrysalids were left uncovered for a few days. 



From work carried out it appears to be definitely proven that this 

 pest is parasitized during the chrysalis period and is free from para- 

 sites during the entire caterpillar stage. 



Owing to unavoidable causes these observations on B. isthmia have 

 not been as complete as could have been wished, but they cover the 

 ground as thoroughly as the circumstances would permit. 



I wish to express my thanks to Dr. S. T. Darling, former Chief of 

 Laboratories, for his advice and assistance during nearly the whole of 

 this work; to Major F. F. Russell, Chief of Laboratories, for examin- 

 ing and making cultures of the entomogenous fungi of this pest; to 

 Dr. H. C. Clark for making pathological examinations of chrysalids 

 killed by this fungus disease, and to Mr. J. E. Jacobs, Chemist, for 

 determining all weights given in this paper. 



NOTES ON THE LIFE-HISTORY OF MARMARA ELOTELLA 



BUSCK, A LEPIDOPTEROUS SAP FEEDER 



IN APPLE TWIGS 1 



By Stuart C. Vinal 



For several years the writer has observed quite noticeable serpentine 

 mines in the bark of apple twigs in the vicinity of Amherst, Mass. 

 In 1914 a sample of this work was sent to Washington for determina- 

 tion, and identification showed the sap feeding larva responsible to 

 belong to the genus Marmara of the Tineina but the adult moths had 

 never been reared from apple. Accordingly, at the suggestion of Dr. 

 H. T. Fernald, investigation was started during the winter of 1915 with 

 the object of obtaining adult insects and studying the life-history. In 

 July some moths were bred from the apple twig mines and sent to Mr. 



^ Contribution from the Entomological Laboratory of the Massachusetts Agricul- 

 tural College, Amherst, Mass. This paper is presented as part of a thesis for the de- 

 gree of Master of Science. 



