572 MISS J. Doi*rALT) oisr new and little-known 



This species has been erroneously identified by De Koninck with 

 his M. Archiaciana^ from which it differs by its much smaller size, 

 greater spiral angle, more angular form, the smaller number of its 

 keels, and also their greater relative strength. He evidently con- 

 founds M. angulata, Portl., with M. elongata, Portl., shells which 

 are not only distinct species, but which he also considers belong to 

 different genera. On p. 67 he identifies the former with Worthenia 

 Waageni. In his account of M. Arcliiaciana he refers to the figure 

 of M. elongata and the description of M. angulata, Portl. 



The largest specimen in the Museum of Practical Geology, London, 

 is that figured by Portlock. There are only eight whorls, as the apex 

 is imperfect. Length 19 millim. ; width of body-whorl 8| millim. 



Localities. Dromard, Draperstown ; Ballynascreen, Londonderry. 



Formation. Lower Carboniferous Shales, referred by Prof. Hull 

 to the Upper Calciferous Series. 



In the Museum of Practical Geology there is a shell (PI. XYII. 

 fig. 6) from the Calciferous Sandstone Series of Northumberland 

 (marked R. 106 with a red line) which strongly resembles this and 

 is probably identical with it. It differs slightly in ornamentation, 

 having a fine thread between the sinual band and the lower of the 

 keels on the upper surface of the whorl. Also the upper of the two 

 keels bounding the sinual band appears to be more prominent than 

 on the Irish specimens. The shell is embedded in the matrix and 

 only about eight whorls are visible, of which the length is 21 J 

 millim. ; width of penultimate whorl 8 millim. 



Locality. River Tweed, a quarter of a mile below Coldstream 

 Bridge. 



Formation. Calciferous Sandstone Series. 



Section Ccelocaultjs, CEhl. 



Shell elongated, whorls smooth, sinual band not prominent, sinus 

 shallow. Distinguished from Hormotoma by its flattened whorls, 

 sutures less impressed, and above all by the existence of a narrow 

 but very deep umbilicus. Columella quite vertical, peristome 

 reflected. 



MUECHISONIA (CCELOCATJLTJS ?) TFEDIA, Sp. nOV. (PI. XYII. fig. 7.) 



Shell elongated, conical, composed of more than ten compactly 

 coiled whorls. Whorls smooth, somewhat flattened and separated 

 by sutures, but slightly inclined from the horizontal. Sinual band 

 nearer the anterior than the posterior suture, level with the surface 

 of the whorls, and defined by a very fine thread on each side. Lines 

 of growth strong, curving back to the band above and forwards 

 again below, indistinct on the band, but sufficient to give evidence 

 of a somewhat shallow sinus. Base probably flattened. Mouth un- 

 known. 



I refer this shell to the Section Coelocaulus, (Ehl., on account of 

 its compressed whorls and flat sinual band. As the mouth and base 



^ * Faune du Calc. Carb. de la Belgique,' vol. viii. pt. 4, p. 16. 



