THE DEVELOPMENT OF THE MIRACIDIUIW OF PARAGONIMUS 

 UNDER VARIOUS PHYSICAL CONDITIONS/ 



By Philip E. Garrison- and Ricaedo Leynes.' 

 (From the liioUxjicul Laboratory, Bureau of Science. 



INTRODUCTION. 



Tlie present paper presents observations made during the past two 

 years upon the development of the ova of Paragonimus under various 

 physical conditions. It is in part based upon the repetition on a more 

 extensive scale of the experiments and observations of Manson (1888), 

 Kellicott (1894), Kerbert (1881), Otani (1887), Miura (1889), and 

 Nakahama (1883), and in a large part upon experimental work which, 

 so far as we are aware, has not been previously done. 



The work was undertaken with three practical purposes in mind, 

 namely, to add to our knowledge concerning, first, the prophylactic 

 treatment of jjaragonimiasis, especially as regards the care of infected 

 patients ; secondly, the possibility of introducing the lung-fluke into colder 

 climates; and thirdly, the life-cycle of the parasite, notably, its probable 

 intermediate host. 



With these purposes in view experiments have been made, first, to 

 determine the most favorable conditions for the development of the ova 

 and the time required for such development; secondly, their resistance to 

 varying degrees of temperature and light, to desiccation, and to salt 



solution of various strengths. 



MATERIAL. 



Sputum and faeces containing Paragonimus eggs have been used from 

 about fifteen different patients, one, a patient at the Civil Hospital, the 

 others in the hospital at Bilibid Prison. By far the greater number of 

 experiments have been made with the sputum of a Bilibid prisoner, number 

 3680-P, who for over a year past (when he came under observation) has 

 expectorated daily from 10 to 30 cubic centimeters of blood-tinged, 

 mucoid sputum, heavily loaded with Paragonimus ova. 



'Read at the Sixtli Annual meeting of the Pliilippine Islands Medical Associa- 

 tion, February 13, 1909. 



"Assistant surgeon, United States Navy; detailed medical zoologist to the 

 Biological Laboratory, Bureau of Science. 



* Student demonbtrator in Medical Zoology, Philippine Medical School. 



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