118 GOES, RKTICULAKIAN KHIZOPODA OF THK CARIBBEAN SEA. 



Syu. Amphistegina vulgaris, Lessonii u'Ouii., 18:36, Tabl. nielli., Ann. So. Nut. 7, p. 304, 305; Mod. 40, 



98; t. 17, figg. 14. 

 gibbosa u'Oiui., 1839, Cuba, \,. t'20, t. 8, figg. 13. 



Hauerina, mamillata, rugosa D'OIIH., 1816, For. tert. Victim;, p. 186, t. 12, figg. 



311. 



vulgaris PAIIKEK et JONES et BUAUY, I860, Crag. For.; 1'ul. Sou. 19, t. i!, lijjg. 



4648. 

 minuta BRADY, 1876, Carbonif. and Perm, ibramt'.; 1'al. Soc. 30, p. 146, t. 11, 



fig. 7. 

 ,, Campbelli, Aucklandiea KAH.II., 1865, For. Griinsandst. N. Zeeland.; Novara Kcise, 



geol. Th. 1. 2, p. 8485, t. 16, ligg. 19. 

 ? ornatissima KAKU., 1865, Griinsandst. N. Zcel.; Novara Reise, geol. Th. 1. a, p. 85, 



t. 16, fig. 20. 



Orbicillillil aduiica FIGHT, et MOLL. 



Tab. IX, figg. 304307. 



This handsome and variable species presents itself in deep water promiscuously 

 in both its adunca- and vdrbiculavtori&a. The latter is for the most part flattened out 

 to a singlefioored thin dise, that often shows a few broad radiating impressions on 

 both its sides. Those impressed bands are occupied by somewhat wider subdivisions 

 or chamberlets. 



A Peneropli-foria variety is also met with in company with the common forms. 

 It is impossible to distinguish it from some forms designated as Peneroplis {troteus 

 D'OiiB. from the West Indies, Peneropl. prisca Rss. from the tertiary strata and Pene- 

 ropl. planatus var. Icevigatus KARR., also from the tertiary formation. 



Since no other true distinction between Orbiculina and Peneroplis has been stated 

 than the striation or plication of the surface of the latter, it would be inconsistent 

 with the notion of genus and even of species to distinguish forms, which cannot duly 

 be entitled higher than as to rank of varieties. 



D'ORBIGNY himself admits that les Orbiculines, pour nous, ne sont que des Pene- 

 roples a loges divisees (Hist. d. 1'Ile de Cuba Foraminif. p. 64). On this account it 

 seems justifiable to range f>Peneroplis as a variety under Orbiculina, or vice versa, as 

 the latter may be regarded as a higher developed Peneroplis. 



The striated form, in no way but in this feature differing from young OrbicuUncu, 

 are also met with, but always scanty and in a pigmy state. 



Orbiculina adunca is very common also in deep water, particularly its orbicula- 

 form, which attains a diameter of 6 mm. 



The simple and unstriated form is more rarely met with. 



By examing several specimens whole and in horizontal section 1 have satisfied 

 myself that the outer charnberwalls are perforated with veritable pores of a middle 

 size, now pretty closely arranged and now more scattered. 



Figg. 304 305: quite young specimens. 



Figg. 306 307: peneropliforrn, unstriated Orbiculina adunca, 



