128 



NOTES ON GYRODACTYLUS 



evident and so profound that some measurement of the effects 

 was desirable and a haemoglobin estimation of a series of heavily 

 infected fish together with normal controls was made by means 

 of a Dare haemoglobinometer. For the use of this instrument 

 the writer is gratefully indebted to Professor J. J. R. Macleod. 

 The results appear in the following table. 



RESULTS OF HAEMOGLOBIN ESTIMATION OF BlOOD OF FuNDULUS 



Heteroclitus Heavily Infected with Gyrodactylus 

 WITH A Comparison Series of Normal Fish. 







Length in 



cms. 



Ui 



lemo- 



Serial 



Sex 1 



to base cau- Condition 



globin 



Number 





dal fin 





Reading 



No. 



1 



Female 



4.7 



Heavily infected 





20% 



No. 



2 



Male 



4.2 



Unusually heavy infection 





15% 



No. 



3 



Female 



4.8 



Very heavy infection. 















Fish seemed almost bloodless 



5% 



No. 



4 



Male 



4.9 



Unusually heavy infection 





18% 



No. 



5 



Female 



4.5 



Heavy infection 





38% 



No. 



6 



Male 



4.2 



Heavy infection 





39% 



No. 



7 



Male 



4.1 



Heavy infection 





21% 



No. 



8 



Male 



Less 



than 4. Heavy infection 





51% 



No. 



9 



Female 



3.7 



Heavy infection 





32% 



No. 



10 



Male 



4.7 



Normal 





71% 



No. 



11 



Male 



5.1 



Normal 





62% 



No. 



12 



Male 



5.0 



Normal 





60% 



No. 



13 



Female 



5.2 



Normal 





71% 



No. 



14 



Female 



6.1 



Normal 





68% 



No. 



15 



Female 



6.5 



Normal 





54% 



No. 



16 



Female 



6.1 



Normal 





56% 



No. 



17 



Female 



3.2 



Normal 





82% 



No. 



18 



Male 



6.2 



Normal 





51% 



No. 



19 



Male 



4.7 



Heavily infected 





20% 



No. 



20 



Female 



4.8 



Heavily infected 





15% 



No. 



21 



Male 



4.8 



Heavily infected 





35% 



AVERAGE 



of haemoglobin 



estimation for nine normal 







Fist 

 RAGE 



[ _ 







63 

 25 



.89% 



AVE] 



FOR twelve heavily INFECTED FISH 



.75% 



