Szekessy Vilmos (szerk.): A Magyar Természettudományi Múzeum évkönyve 53. (Budapest 1961)
Pócs, T.: The calculation of the quantitative grade of efficacy of collecting and extracting methods of materials used in zoocoenology
Contracted : Divided by Espressing y from this, we receive the constant of the grade of efficacy of one of the methods : y = X, already expressed in the course of the process : Let the final formula of y be substituted into this : The numerator and denominator multiplied by 1 Simplified by C, the final formula reads as x This formula shows the grade of efficacy of the other method applied. The value JB of the formulae is, as pointed out above, the quotient of the second and first numbers of individuals received in the course of our investigations, while C is the quotient of the second and first numbers of individuals gained by applying the methods in a reverse order in the course of investigations on the second sample. For the application of the formulae let an investigation serve as an example, done by a manual selecting and a floating by fatty alcohol sulphonate of sifted litter, containing mollusks. After poisoning, the sifted soil sample was wholly desiccated, therefore I was able to receive all shells by a single floating, and thus it was unnecessary to refloat the residue. Dividing the material into two parts, I first let one of the parts float in a water solution of 4 g/Iiter fatty alcohol sulphonate for 16 hours. There were 246 mollusks in the float. After a complete desiccation of the deposit, I selected it by hand, receiving by this method 30 specimens. Quotient ,,-B" is therefore : The other portion of the material was first manually selected, receiving thus 108 specimens. The residue was then floated, with a resultant 119 shells in the float. Quotient „C" is therefore :
