CHARACTERISTIC DEEP-SEA TYPES. — RHIZOPOD*. 



L69 



walls, the greatest variety of forms and of deviation from the 

 parent type results. 



Pulvinulina auridUla (Figs. 515, 515 a) is a handsome hya- 



Fig. 515. Fig. 515 a. 



Pulviuuliua auricula. : y 5 . (Goes.) 



Fig. 516. Fig. 517. 



Pulvinulina Menardii. \f. (Goes.) 



line species, and its ally, P. Menardii (Figs. 516, 517), is one 



of the most common deep- water species. It is also pelagic. 

 Another deep-water form is Truncatulina Un- 

 geriana. (Fig. 518.) The little Polytrema 

 miniaceum (Fig. 519) is a delicate red parasitic 

 foraminifer, occurring 

 everywhere in the 

 West Indies, which 

 resembles certain mi- 

 nute corals. It has a 



long geological history, dating back 



to the devonian. Of the Nummuli- 



nidae, Polystomella erispa is one of 



the most abundant West Indian types 



J L Fig. ol9. — Polytrema minia- 



of moderate depths. t-eum. y> 



Fig. 518. — Trun- 

 catulina Ungeri- 

 ana. lj 5 . ( Goes. ) 



