Manchester Memoirs, Vol. Ixii. (19 17) 15 



S. tenuis as compared with other Miliolids. We have observed 

 this in other fossil deposits, as in the Miocene clays of Malta 

 in which S. tenuis is common and well preserved, while other 

 Miliolids are represented by pyritic casts only.) 



Genus Pentellina, Munier-Chalmas. 



23. Pentellina ljevis, sp. no v. 



PI. I, fig. 1. 



Test elongated, five to seven chambers visible externally, 

 periphery angular, the chambers being oval in transverse 

 section and each having its own entire enclosing wall. Texture 

 smooth and glistening, unornamented. Length, .75 to .95 mm. 

 Breadth, .43 to .47 mm. 



This rare form has been assigned on account of the arrange- 

 ment of its segments to the genus Pentellina although it has 

 the ordinary Miliolina aperture and does not exhibit the Trema- 

 tophore which is characteristic of P- saxorum -and P. tour- 

 noueri. There may be a question whether it is worth while 

 making a special genus for those Miliolids which, though 

 possessing the arrangement of chambers as provided for in the 

 genus Miliolina possess a more complicated or more fully 

 developed form of oral aperture. 



24. [Miliolina angularis, Howchin.] 



24A. Pentellina attenuata, sp. nov. 



PL VIII, figs. 1 and 2. 



Test very much elongated, five chambers visible externally, 

 periphery angular, chambers flatter and longer in proportion 

 to their width than in P. Icevis. Texture smooth. Length, 

 1 to 1.25 mm. Breadth, .27 to .3 mm. 



This species is rather more rare than P. Icevis, and is easily 

 distinguished from it by its much greater length and more 

 slender proportions. The shell-wall is so fragile through de- 

 composition that I have been unable to find a perfect specimen, 

 and though the drawing here given is to a certain extent a 

 restoration it may be taken as representing a typical specimen. 

 The species has only been found in the beds of marl at the end 

 of the sea-wall and is not plentiful there, only about a dozen 

 specimens being found. 



(Halkyard subsequently found many more specimens, most 

 of which are perfect and are well represented by his figure. 



