GASTEROPODA. 21 



PLEUROTOMA PANNUS, Basterot. 2nd Sup., Tab. Ill, fig. 6. 



PLEUROTOMA PANNUS, Bast. Foss. du Sud-ouest de la France, p. 63. 



Bellardi. Monog. delle Pleur., p. 27, tav. ii, fig. 2. 

 DUMONTII, Nyst. Beige Foss., p. 527, tab. xlii, fig. 4. 



Spec. Char. "P. striis transversis, numerosis, minutis ; striis incrementi decussatis." 

 -Bast. 



Axis, f ths of an inch. 



Locality. Cor. Crag, near Orford. 



France : Saucats, Le'ognan, Dax. 

 Piedmont : Torino, Colli Tortonesi. 



The specimen figured, which, however, is not quite perfect, was found near Orford 

 by Dr. von Konen ; and he has kindly sent me a specimen of the same species from 

 Antwerp, which seems to correspond with our Crag shell. Mr. A. Bell has introduced 

 this name into his list of Coralline Crag shells, so that probably several other specimens 

 may have been found, but that in my possession is the only one from the Crag that I 

 have seen. PL catenata of Mr. Bell strongly resembles it, and may be only a variety. 



As with so many species of this variable genus, it is difficult to say whether the 

 distinctive features which induce authors to make specific distinctions are in the present 

 case constant ; but the identification of the shell by so good a conchologist as Dr. von 

 Konen, and the production by him of a specimen from Antwerp identical in character 

 with our Cor. Crag specimen, gives me more confidence in the present identification 

 than I should otherwise entertain. 



The specimen figured as No. 1 of Tab. Ill was sent to me by Dr. Reed, and has a 

 label attached with the name of Borsonia prima assigned by Mr. A. Bell, who gives for it 

 the locality of " Red Crag, Waldringfield." The shell looks like a deformity, and the 

 ridge upon the columella accidental, as it is angular in form, and like a simple projec- 

 tion. The shell is much abraded, and appears like a mutilated specimen of Pleurotoma 

 turrifera, Nyst (P. turricula of Brocchi, figured in ' Crag Moll.,' Tab. VI). As the 

 name Borsonia prima may, perhaps, be introduced into lists of shells from the Crag, I 

 think it best to give a figure of the specimen, to enable others to judge for themselves. 



Borsonia prima, Bellardi, ' Monog. Pleurot. Toss.,' pi. iv, fig. 13, is, I think, a 

 different shell altogether. 



A specimen of Pleurotoma from Boyton has been very recently sent to me by 



