EFI I < TS OF CARBUX DIOXIDE. 



"i DIIIERKNT TENSIONS OF CARBON DIOXIDE ON 

 1 KIUN ORTHOPTERA (GRA--HOITI i 



JOSEPHINE ALBERTA \VII.I !- 

 v DEPARTMENT. UNIVERSITY OF PENN*YI.\ AM v. 



INTRODUCTION. 



Much attention has recently been given to the ph\>io!i.-iral 

 eileii- nt carbon dioxide upon mammals, while comparatively 

 little information in this respect seems to exi-t \<>r imertebr. 

 I. nise of this lack of data it seemed desirable i<> -tudy the 

 pliy-ioli -:<ical significance of this gas for certain in-et -t-. The 



-ent paper is based upon a quantitative study of tlu- rt -i-t.iiu x- 

 of the grasshopper to different tensions of carUm din\idr imtin^ 



:i<ul.irK - the muscular movements cli>pl.iyrd undrr tlu- 

 inlluence of the gas, the rate of recovery from it- eff< md 



iratory changes in an enclosed space, as mca>unl |,\ c.irbon 

 dii '\idi- and oxygen changes. 



I wish to thank Doctor J. H. Bodine, under whose direction the 

 u-rk was done, for suggestion of the problem and t<>r in-pirinv; 

 nil ii i-in throughout. 



M \TJ KIAI, AND METHODS. 



I 1 h.i- liri-ii >hu\vn iii a recent paper by Doctor Bodinc- i ij that 

 .;r.ilio|)pfi - have a relatively high rate of carl><'ii din\id- i nit put 

 .md tlii> I'.ii-i -ii^gestcd that they might be favorable iii.iu-rial for 

 determining ><une of the eflfects of carbon dioxide on injects. In 

 i ,u i \ in- out the following experiments two specie of Mcltnioplus 

 \\i-rr ux-d : Melanoplns differenti&lis and Mclanoplus femur 

 rnbrnni. 



Ina-much as the methods employed are so varied, individual 

 ripiion- are given under each of the several experiment-. 



1 Data in this pajn-r taken from a thesis submittfl t" tin- laculty ni tlic (irail 



"1 ni' tin- Univi-r.sity of Pennsylvania in partial fulfillment m tin- n-'[u:i. in. nt-; 

 \r tin- ill -j;t. . : \l .-.: r of Science. 



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