58 HALKYARD, Fossil Foraminif era of the Blue Marl 



115. Lagena acuticosta, Reuss. 



Lagena acuticosta, Reuss, 1861, Sitz. k. Ak. Wiss. Wien, vol. 



XLIV, (1), p. 305, pi. I, fig. 4. 

 L. acuticosta, Brady, 1884, Chall. Rep., p. 464, pi. LVII, figs. 



31, 32; and pi. LVIII, figs. 20 and (?) 21. 



Very rare, but typical sub-globular with strong costse. 



(The two specimens should we think be referred to L. 

 costaia, (Will.).) 



116. Lagena williamsoni (Alcock.) 



Eniosolenia williamsoni, Alcock, 1865, Proc. Lit. Phil. Soc. 



Manchester, vol. IV, p. 193. 

 Lagena ivilliamsoni, Balkwill & Wright, 188^, Trans. Roy. Irish 



Acad. vol. XXVIII (Sci.), p. 339, pi. XIV, figs. 6-8. 



Common. The specimens are not always typical, the hexa- 

 gonal marking of the neck which is characteristic of the species 

 being in some cases absent, or often reduced to the merest 

 trace. Under these conditions the specimens are hardly distin- 

 guishable from L. acuticosta, Reuss, as the costse are few in 

 number and of comparatively great elevation. The shells are. 

 however, pyriform and the grooves between the costse are 

 sectionally an arc of a circle. The costae do not run into one 

 another at the base of the shell, but abut upon the circumference 

 of a small raised ring. When the hexagonal pitting of the 

 neck can be discerned the specimens undoubtedly belong to 

 Alcock's species, and in the other cases the difference is so slight 

 and so filled up by innumerable inseparable gradations that 

 there is no need to insist upon the presence of that feature. 

 The best published figure of this species is that given by Balk- 

 will & Wright, which is an excellent one. Their figure shows 

 that the number of the costae is about eighteen. My examples 

 have from 8 to 13. 



(A large proportion of the specimens are absolutely desti- 

 tute of the hexagonal markings round the base of the neck 

 which form the characteristic feature of the species, and should 

 therefore be ascribed without hesitation to the earlier named 

 L. acuticosta Reuss.) 



ii6a. [Lagena striato-punctata, Parker & Jones] 



[Lagena sulcata var. striato-punctata, Parker & Jones, 1865, 



NAAF, p. 350, pi. XIII. figs. 25-27. 

 Lagena sulcata, var. striato-punctata, Brady, 1884, FC. p. 468, 



pi. LVIII, figs. 37, 40. 



