550 



DE. CARPENTER'S RESEARCHES ON THE FORAMINIFERA. 



Pig. I. 



These spines are usually few in young specimens, and become numerous with age ; but 

 this rule is by no means constant, since full-grown specimens are occasionally met with 

 having no more than four or five very short spines (Fig. III. H). The spines are usually 

 either cylindrical or somewhat club-shaped, the latter form being the more common; 

 but we occasionally see them showing a tendency to bifurcation at their extremities ; 

 and they not unfrequently appear as if two, three, or even four spines had coalesced to 

 form one, this being indicated not only by its unusual size, but by the mutual divergence 

 of its components as they extend themselves from the central disk (Fig. I. B, and Fig. II. F). 

 A somewhat remarkable contrast in the relative 

 development of the disk and of the spines is pre- 

 sented by the general aggregate of the Philippine 

 and Mediterranean specimens placed in my hands 

 by Mr. CUMIEXJ; as is shown in comparing Figs. II. 

 and III. It is in the former (Fig. II.) that we meet 

 with the greatest number as well as the greatest 

 relative length of the spines ; and that the bifurca- 

 tion or trifurcation of their extremities presents itself. 

 In full-grown specimens of the Philippine Calcarina, 

 we commonly find the spines diverging from the 



Two specimens of Philippine variety 

 of Calcarina, distinguished by unusual 

 exuberance of spinous outgrowths. 



Kg. II. 



Kg. III. 



Outline-representations of various specimens 

 of Philippine variety of Calcarina. 



6 H 



Outline-representations of various specimens of 

 Maltese variety of Calcarina. 



