92 THE FORAMINIFERA 



Miocene of Muddy Creek (Victoria), and the Pliocene 

 of St. Erth, of Suffolk, and Italy. Uijpei' Cretaceous 

 to Recent. (Plate 3, fig. D.) 



M. (Quiiiquelociilina) seiuinulum, Linne sp. 

 {Serjnda seminuhnn), ' Syst. Nat.' 1758, ed. x. 

 p. 786 ; Gmelin's (xiii.) ed. 1788, pp. 37, 39. 



This is one of the Miliolince which shows portions 

 of five chambers on the surface of the shell (hence 

 Quinquelociilinci). It is generally looked upon as a 

 central type of the group, and it is one of the most 

 widely distributed of the family, both as to locality 

 and depth ; regarding the latter it is found down to 

 3,000 fathoms. M. seminulum was one of the earliest 

 figured species of the genus, and was formerly 

 described as a serpula, on account of its contorted 

 and wormlike appearance, although, comparatively 

 speaking, of very minute size. This species ranges as 

 a fossil from the Loiver Eocene upwards. (Plate 3, 

 figs. E, e.) 



The genera, or rather sub-genera, established by 

 Munier Chalmas and Schlumberger by means of their 

 work upon the internal appearance of the test in 

 transverse section of the megalospheric form are as 

 follows : — 



Dillina, TrilocuUna, TriUi?ia, Qiiinqueloculina, 

 Pentellina, IclaUna^ Adelosina, PerUocuUna, Massi- 

 lina, Seterillina, Sigmoilina. 



Thus, for example, Massilina is distinguished by 

 having a quinqueloculine arrangement of chambers 

 surrounding the megasphere, which are followed by 

 a series of chambers disposed in one or two planes, 



