66 



BULLETIN 161, UNITED STATES NATIONAL MUSEUM 



Test much compressed, circular in outline, the early chambers in 

 the microspheric form coiled planispirally, soon widening and be- 

 coming annular, in the megalospheric form the annular chambers 

 beginning at once after the large rounded or oval proloculum; cham- 

 bers in two layers in the adult, and each divided into many chamber- 

 lets, the chamberlets of each newly added series alternating with 

 those of the preceding series; wall imperforate except in the proloculum 

 and succeeding chamber which are finely porous; apertures at the 

 periphery of the chamberlets in a double series as are the chamberlets. 



Table 32. — Amphisorus hemprichii — material examined 



Tliis species is the most widely distributed of this particular group 

 in the material we have examined. It is best developed in shoal 

 water, probably being an attached form in this area as it is in the 

 West Indies. There are, however, numerous specimens, usually 

 either worn or small, in the Albatross collections. These probably 

 represent specimens which have been carried out into deeper water by 



