THE FAMILY MILIOLID.E 83 



or free. When attached, the form of the segments 

 is plano-convex, but when free they assume a 

 normal subcylindrical form. The commencement of 

 this species often has an arrangement of chambers 

 like that of Miliolina, by which it shows an affinity 

 with Articulina. 



By an error in determining its source A^. tihia has 

 often been quoted as a Triassic fossil. It first makes 

 its appearance in the Lias, where it often occurs in 

 company with oN^. Jiicifuga. In recent dredgings 

 N. tihia is a shallow-water organism. L/V/s, Oolite^ 

 Becent. (Plate -2, fig. 4.) ' 



8uh-family 2. Miliolinin.e. 



Test coiled on an elongated axis, having two 

 chambers in each complete whorl, either opposed and 

 on a single plane of symmetry, or disposed at various 

 angles round the longer axis. Aperture alternately, 

 during growth, at either end of the shell. 



Genus Biloculiiia, D'Oebigny. 



The chambers are arranged in a single plane, the 

 last two only being visible. The internal structure 

 of the microspheric form often has a quinquelocu- 

 line commencement. The aperture is usually 

 crescentic, enclosing a valve-like projection, normally 



' For references to other species of this genus and those that follow 

 consult Sherborn's Index to the Genera and Species of the Foraminifera. 

 Only one or two important types of each genus can be given here, on 

 account of the limits of space. 



G 2 



