THE FAMILY EOTALIIDiE 217 



a deep mnbilical vestibule with which each chamber 

 communicates by a neck. Complanate forms with 

 a row of pores along the septal depressions of the 

 inferior surface. Pelagic type with large inflated 

 chamber covering the base of the shell. JJ-pper Cre- 

 taceous to Recent. 



Example. — C. Poeyi (D'Orbigny), (Bosaliiia), 

 'Foram. Cuba,' 1839, p. 100, pi. iii. figs. 18-20. 



This is a common species in the coral sands of 

 low latitudes. It appears to be commonest in 

 shallow water, but is found down to a depth of over 

 600 fathoms. Some of the varieties of this form are 

 often found growing attached to seaweed. In fresh 

 specimens the test, especially the apical portion, is 

 stained a deep brown or purplish red, with the 

 sarcode. Becent. (Plate 12, fig. C.) 



Pelagic Type. 



C. {Tretomphalus) huUoides (D'Orbigny), 'Foram. 

 Cuba,' 1839, p. 104, pi. iii. figs. 2-5. 



The chief difference in this form is the large 

 inflated chamber which is developed from the 

 inferior surface of the test of an ordinary Gymhalo- 

 pjora of the variety squamosa'. 



This pelagic modification is particularly interest- 

 ing on account of the frequent occurrence of 

 embryonic shells living within the balloon-like 

 chamber, and which are liberated through an ento- 

 solenian orifice. Becent. (Plate 12, fig. D.) 



