96 



BULLETIN 71, UNITED STATES NATIONAL MUSEUM. 



I have had material from off the Hawaiian Islands, from Hong- 

 kong Harbor in 10 fathoms, from Cagayan, Sulu Islands, Philippines, 

 and from Tuscarora station 60, in latitude 21° 14' N.; longitude 157° 

 36' W. in 63 fathoms. 



The species is very abundant in shallow waters of the East Indian 

 region. 



In the very large specimens with thickened edges the megalospheric 

 young are often found in the outer chambers of the parent test. 

 In these young four of which are figured here, there is an oval pro- 

 loculum of very large size, followed by a second, Cornuspira-hke 

 chamber of about a quarter coil in length. This is, as usual, con- 



Fig. 49-52.— Young specimens of Orbitolites complanata, taken from same "mother" cell, X 36. 



P. PROLOCULUM, C, CORNUSFIRA-LIKE SECOND CHAMBER, 3 THIRD CHAMBER ABOUT WHICH THE FIRST 

 ANNULAR CHAMBER DEVELOPS. 



tinuous with the wall of the proloculum and builds no floor. Instead 

 of being evenly curved its outer end often has a tendency to swing 

 away from a uniform curve and to suggest the tangential direction 

 seen in much later stages of the other two species discussed, thus 

 initiating a character of later growth as early as the second chamber. 

 The third chamber instead of being like the third chamber of the 

 other types of the group is nearly an annulus, its ends not quite 

 meeting on the peripheral wall of the second chamber. This point of 

 contact as will be seen in the four specimens here figured is very 



