HYALONEMA (PHIALONEMA) PATERTFERUM. 



375 



respectively, m, The average proportion of the anchor-length to the anchor- 

 breadth of the large micramphidiscs is in form C 100 to 92, in the forms D, E, 

 and F 100 to 72-76. According to Wilson {loc. cit.), the length of the anchors 

 of these spicules is, both in forms A and B, a third of the length of the whole 

 amphidisc; the anchors of these spicules are in these two forms therefore 

 probably also about equal in respect to the proportion between length and 

 breadth, n, In forms A and B the length (20-25 m) of the small micramphidiscs is 

 equal. In forms C and D these spicules are larger, most frequently about 26 and 

 24 IX long respectively. In forms E and F they are smaller, most frequently 

 about 20 and 21 ju long respectively, o. The average proportion of anchor- 

 length to anchor-breadth of the small micramphidiscs is in form D 100 to 153, 

 in form C and F 100 to 140, and in form E 100 to 1 14. In the forms A and B this 

 proportion is not known. 



The affinities of the six different forms in respect to these further qualities 

 are tabulated below: — 



According to this table the units of all the fifteen possible pairs of forms, 

 with the exception of those of two, coincide with respect to only 1-4 of the 



