ANALYSIS OF DATA 79 



VARLATION IN RESPIRATORY RATE WITH SEASON 



Mollusca 

 Pelecypoda 

 Mercenaria mercenaria: Gill, mantle, muscle; in general, endogenous respiratory rate highest 



in winter and early spring and lowest in August and September; Hopkins, 1946 

 Pinctada martensii: Gill; rise in endogenous respiratory rate from June to the middle of January; 

 Kawai, 1957 



VARIATION IN RESPIRATORY RATE WITH SALINITY 



Mollusca 

 Pelecypoda 



Mercenaria mercenaria: Gill, mantle, increase in endogenous respiratory rate with lowered 

 salinity; adductor muscle, decrease in rate with lowered salinity; Hopkins, 1949 

 Arthropoda 

 Crustacea 



Carcinus maenas: Gill; increase in endogenous respiratory rate with lowered salinity; Pieh, 1936 



EFFECTS OF VARIOUS IONS ON RESPIRATORY RATE 



Mollusca 

 Gastropoda 

 Helix aspersa: Heart; rise in endogenous respiratory rate with increasing concentration of K"*" 

 ion, compared to the concentrations of Na+, Ca"'"'', and Mg "'""'"; Cardot, Faure, and Arvanitaki, 1950 

 Pelecypoda 



Mytilus galloprovincialis: Ventricle of heart; same as above; Cardot, Faure, and Arvanitaki, 1950 

 Cephalopoda 

 Sepia officinalis: Nerve; same as above; Cardot, Faure, and Arvanitaki, 1950 

 Arthropoda 

 Crustacea 

 Libinia emarginata: Claw nerve; rise in endogenous respiratory rate with increasing concentra- 

 tion of K"*" ion to a maximum at 40 mM K^, then sharp drop in endogenous respiratory rate; 

 Shanes and Hopkins, 1948 



GRADIENT OF RESPIRATORY RATE ALONG LONG AXIS OF BODY 



Annelida 

 Clitellata 

 Eisenia foetida: Viscera and body wall; U-shaped gradient in the endogenous respiratory rate 

 and in succinoxidase activity along the long axis of the body; O'Brien, 1957 

 Octolasium cyaneum: Body wall; U-shaped gradient in succinoxidase activity; O'Brien, 1957 

 Arthropoda 

 Insecta 

 Periplaneta americana: Prothorax, mesothorax, metathorax, abdomen; decrease in endogenous 

 respiratory rate from prothorax through metathorax, and then a rise in respiratory rate in 

 abdomen; Kubista, 1956 



GRADIENT OF RESPIRATORY RATE ALONG A NERVE 



Arthropoda 

 Merostomata 

 Limulus Polyphemus: Optic nerve; at 31° and 28° C, endogenous respiratory rate highest in 



