HYALONEMA (PRIONEMA) CRASSUM. 



281 



fall into two groups, large and small ones. These two groups are very clearly 

 distinguished, there being no amphidiscs 62-159 n long. This absence of inter- 

 mediate amphidiscs finds its expression in the adjoined graph in the large gap of 

 the curve between 72.89 and 129.13. The amphidiscs the lengths of which are 

 represented by the curves to the right of the gap belong to the morphological 

 groups 1 and 2. The two curves overlap considerably. The amphidiscs to 



Smooth \ Macramphidiscs. 

 Serrated J 

 Micramphidiscs 



e 



3 



z 



20 



15 



10 



Micramphidiscs 



Small 



Lai'ge 



T-r 



TT 



I f I 1 



Macramphidiscs 



Serrated 



/ " V 



Smooth 



---J: 



T-TT 



00 

 — ; CM 



00 





r-i CO Ln 



.-; c\i in 



^ H LO 



CM CM CM 



o 

 o 



CO 



r-l CM 

 .-J LO 



GO •-' 

 t^ 00 



c; CM CM en CO -r 



CM p !>; CO .-; p 



00 t--^ CD t--^ cri c^j 



00 OM O ■— 1 CM 'S- 



LO t^ 

 CM 00 



M 



c 



oLoL i I I M i I 1 I 1 11. I I M I I I 1 I ! I 1 M , 



<£>cr> cMcoL.oair-(coinOi— ioo-^iDoou3^ooooocMCMCjMro'*Lnt^ 

 T— icM'^. °Q'^'~!'~!'^^'~:'^'— ?'^'~i'^f~:'>:CMCMoq'-;cMpt-;CO'— <pCMoq 

 »-Ht-MT^tot^cS--HCOLOodo^t^i-HLOC^'^oocMOo6i>^^r^a^c^i^^ 



rtr-ir-i.-(CMCMCMCMC0.C0C0-«l-^^L0OOf^0000CJ5Oi-iCM'*Lnt^ 



"* "* 00 LO 



O CO CO o 

 CO CO CO ■<* 



Fig. 13. — Amphidiscs. 



which the curve to the left of the gap pertains are those of the morphological 

 groups 3 and 4. There is a conspicuous depression in this curve at 37.40- 

 41.14, corresponding to the absence of amphidiscs 37-41 n long. This depres- 

 sion may be taken as the limit dividing the (smaller) amphidiscs of the mor- 

 phological group 4 from the larger ones of group 3. 



