R. 31. Brydone— Chalk Poli/zoa. 15} 



It occurs very sparingly in the Act. quadratus zone of Hants and 

 the Isle of Wight, and at Trirningham. 



Pavolunulites subquadrata, sp. now PL X, Pigs. 7-9. 



Zoarium free, unilaminate ; my specimens range from 3 "4 mm. by 

 3-6 mm. up to 6-5 mm. by 8-1 mm., the back covered with numerous 

 prominent flattened radiating ribs, many of which show a faint median 

 furrow. 



Zocecia small, average length -o-bo mm., breadth •Sb-'ib mm., 

 arranged in slightly diverging rows; intercalated rows beginning with 

 a vibracularium ; aperture nearly terminal, rather longer than wide, 

 and slightly wider below than above, corners rounded below and 

 square above ; two little nicks in the margin may often be seen at 

 the head of the zooecium. 



Ocecia short and wide, only partially attached by the under side and 

 with the free edge deeply cut back into a semicircle. 



Vibracularia shallow, with a long narrow aperture tapering above 

 to a rounded end, but below to a pointed end ; above the aperture the 

 front wall does not rise, but abuts at some depth against the succeeding 

 zooecium. They are sometimes vicarious. 



Common in the upper part of the II. cor-testudinarium zone on the 

 Sussex and Isle of Wight coasts, and I have also found it at the same 

 horizon in Hants. I believe it to be confined to this zone. 



A friend has pointed out that I have nowhere mentioned that my 

 photographs are touched up before reproduction. This is a fact and 

 I have found it inevitable, as the shortness of focus of the camera 

 and the irregularity of surface of the fossils make it hopeless to expect 

 photographs sharp enough to be really illustrative. To demonstrate 

 this 1 have for this and the succeeding species given an exceptionally 

 good photograph au naturel and a much inferior one touched up, 

 and I do not think there can be any doubt which is which, or which is 

 the more precise. 



Lunt/lites Marssoni, nom. nov. PL X, Pigs. 10-12. 

 Syn. Semieschara crassa, Beissel, op. cit., p. 42, pi. iv, figs. 47-50 ; Marsson,. 

 op. cit., p. 75. 



Pragments of a form corresponding closely with Beissel's figures of 

 Semieschara crassa are not uncommon at Trimingham. The only 

 points in which they differ are that the posterior slit in the 

 vibraculai'ia has become a wide deep-set opening and that the aperture 

 of the vibracularia has become more or less pointed anteriorly, points 

 which do not appear to justify even varietal recognition. One or two 

 of my larger fragments would strongly suggest that they are parts 

 of a Lunulite, and fortunately I have obtained one practically perfect 

 circular Lunulitine specimen, whose diameter is about 9 - 7mm. 

 Xo doubt the deep irregular depressions exemplified in Pig. 12 form 

 lines of weakness along which large specimens break readily. Un- 

 fortunately there is already a Lunulites crassa (Tenison-Woods, Trans. 

 Hoy. Soc. S. Austr., iii, p. 5), and I have renamed the species after 

 the second of the only two authors who refer to it, the name of the 

 first not beinc; available. 



