144 



TAOE SKOGSBERf; 



'^^W 



~y 



Fiu-. XXIII. — iMiiyraiii lo slidw \\w i-fsulls of my measuicnicnts of thr- lengths of the slu-Us of a iimiiht'r of spt'cimcus 

 of Kiiihe sp. from YillefraiRiie-s-iner. The abscissa represents I lie lenuUis of the shells expressed in divisions of a 

 iniirometer (64 divisions = 1 mm.): all the measurements are rounded off lo the nearest half division. The ordinate 



represents the number of the .specimens measured. 



The relation between tlie different succeeding stages, i. e. the g r o w t li - f a c t o r s, 

 is as follows: 



45.1 : 36,12 = 1,248 

 36,12: 28,8 = 1,254 

 28,8 : 23,23 =^ 1,24 

 23,23: 19,2 = 1.21 



19.2 : 15,5 -= 1.24. 



//-„.• do ihr^e ,-i-am- How do the examples given by me above stand in relation to Brooks's law, if the 



pie, ,tand uireiatwn ^j^^^g^. jg ^^^^^ ^g formulated bv ft. H. FowLER, 1909, p. 224? 



tn lirdolis's Imv? ' i i i i i j_ i j_i 



(hipridina (Doloria) vecHnata: The agreement between the lengths as calculated theo- 



h'r/ni-plrs in jnv.,iir Jl \ ' f o o • , , 



„i th,\- Uhv. rctically and those actually found is striking. The males increase, however, comparatively less 



