MOOK. VARIATIOX IN SPIRIFER MUCRONATUS 



191 



Spirifer mucronatus mut. thedfordense — Continued 



Adult Stage 



N^anic Stage 



A 



Number Width 



43 29mm. 



44 31 



45 27.5 



46...!. 32 



47..... 29 



48 33 



49 32 



50 30 



51 29.5 



52 37 



53 31 



54 37 



55 30 



56 32 



57 28 



58 32 



59 33 



60 27 



61 30 



62 27 



63 34 



64 40 



65 33 



66 39 



67 29 



68 40 



69 



70 40 



ri 38 



72 28 



73 35 



74 39 



75 34 



76 32 



77 26 



78 29.5 



79 29 



SO 29 



81 31 



82 29 



S3 28 



84 32.5 



85 31 



86 



87 34 



Height 



26mm, 



30 



29 



25 



26 



25 



24 



25 



22 



26 



27 



24.5 



24 



25 



21 



23.5 



26 



23 



26.5 



26 



23 



25 



24 



30 



24.5 



21.5 



29 



27 



21 



26 



25 



29.5 



26 



25.5 



24 



25 



25.5 



25 



16 



15 



21 



25 



20 



Index 



(reverse) 



.896 

 .967 

 1 . 054 

 .781 

 .896 

 .757 

 .750 

 .833 

 .745 

 .702 

 .870 

 .662 

 .800 

 .781 

 .750 

 .734 

 .787 

 .851 

 .883 

 .962 

 .676 

 .625 

 .727 

 .769 

 .844 

 .537 



.725 

 .710 

 .750 

 .742 

 .641 

 .867 

 .812 

 .980 

 .813 

 .862 

 .879 

 .806 

 .551 

 .535 

 .646 

 .806 



.588 



Index 



1.11 

 1.03 

 .94 

 1.28 

 1.11 

 1.32 

 1.33 

 1.20 

 1.34 

 1.42 

 1.14 

 1.51 

 1.25 

 1.28 

 1.33 

 1.36 

 1.26 

 1.17 

 1.13 

 1.03 

 1.47 

 1.60 

 1.37 

 1.30 

 1.18 

 1.86 



1.37 

 1.40 

 1.33 

 1.34 

 1.56 

 1.15 

 1.23 

 1.01 

 1.22 

 1.16 

 1.13 

 1.24 

 1.81 

 1.86 

 1.54 

 1.24 



1.70 



Width 



29mm. 



31 



27.5 



32 



29 



33 



32 



30 



29.5 



37 



31 



37 



30 



32 



28 



32 



33 



27 



30 



27 



34 



40 



33 



39 



29 



40 



40 



38 



28 



35 



39 



34 



32 



26 



29.5 



29 



26 



31 



29 



28 



32.5 



31 



34 



Height Index 

 (reverse) 



20. 5mm.. 706 



21 



20 



18 



17 



17 



19 



18 



14 



18 



20 



15.5 



19 



15.5 



16 



18 



19 



15 



17 



16 



18 



19 



17 



20 



18.5 



17.5 



24 



20 



17 



17.5 



18.5 



21 



20 



15 



13.5 



17.5 



15.5 



17 



12 



11 



17.5 



19.5 



15 



.677 

 .727 

 .562 

 .586 

 .515 

 .593 

 .600 

 .474 

 .432 

 .645 

 .418 

 .633 

 .484 

 .571 

 .562 

 .575 

 .555 

 .566 

 .592 

 .529 

 .475 

 .515 

 .512 

 .638 

 .437 



.600 

 .521 

 .607 

 .500 

 .474 

 .617 

 .625 

 .576 

 .457 

 .603 

 .596 

 .548 

 .413 

 .392 

 .538 

 .629 



.441 



Index 



1.44 



1.47 

 1.37 

 1.77 

 1.70 

 1.94 

 1.6S 

 1.66 

 2.10 

 2.05- 

 55 

 38 

 5T 

 06 

 75- 

 77 

 73 



1.80 

 1.76 

 1.68 

 1.88 



2.ia 



1.94 

 1.95 



i.m 



2.28 



1.6^ 



1.90 



1.64 



2.00 



2.10 



1.61 



1.60 



1.73 



2.18 



1.65 



1.67 



1.82 



2.41 



2.54 



1.85 



1.58 



2.26 



