22 Scientific Proceedings, Royal Dublin Society. 



of England. It differs from that species as follows:— Smaller size; major 

 septa fewer, shorter ; minor septa scarcely developed ; vesicular zone 

 rudimentary. 



Camarotoechia aff. mitcheldeanensis, Vau. 



This only differs from Vaughan's species in having usually 4 ribs on the 

 fold and .3 in the sinus, and in its slightly larger size. The internal structure 

 is essentially the same. 



Athyris cf. glabristria, Phill. 



There are two distinct forms included under this description : — 



(a) A gibbous shell, whose fold and sinus appear early and become 

 extremely marked with age. It seems to agree with the one figured by 

 Garwood as the index of his zone A.^ 



(5) A larger, more depressed shell, whose fold and sinus appear late, and 

 only cause a slight undulation in the valve intersection. This is evidently 

 the form referred to by Vaughan as A. lamellosa-glabristria? 



Both forms vary considerably, but I have not found a full-grown individual 

 that could not be unhesitatingly referred to either (a) or (J). Both are usually 

 transverse. The ornament of both is the same, and is like Davidson's Plate 

 XVllI, fig. 10, there being about two fringes per millimetre. The narrow 

 lamellae, where the fringe is stripped off, show an alternation in strength, 

 one, two, or three weak ones occurring between two stronger ones. Strongly 

 marked growth halts, as noted by Vaughan, occur in both. 



Form a is abundant at two different levels — M 1 and M 8, 9 (and their 

 repetition M 12). Form h is abundant and large throughout M 1, 2, 3, and 4. 



Seminula cf. aiiibigua, Sow. 

 M 5 = Z^. 

 This is a very small shell. The largest specimen had the dimensions : — 

 Length, 12 mm. ; width, 14 mm. ; depth, 5 mm. The proportions are approxi- 

 mately as in Davidson, Brit. Garb. Brach., Plate XV, fig. 17, but the beak is 

 sharper and less arched. 



Previous Work on the Section. 

 The late Dr. Vaughan intended at one time to publish an account of the 

 Malahide fauna. He has referred to it in the Burrington and Belgian papers.^ 

 In these the following fossils and horizons are mentioned as occurring at 

 Malahide : — 



1 Proo. Geol. Assoc, vol. xxvii, PI. xii, fig. 3. 



2 Q. J. G. S., vol. Ixxi, 1915 (' Belgian Paper), p. 16. 



2 Reynolds and Vaughan, Q. J. G. S., vol. Ixvii, 1911. Vaughan, Q. J. G. S., vol. 

 Ixxi, 1915. 



