44 SUPPLEMENT TO THE CRAG MOLLUSCA. 



Pleurotoma equalis, S. Wood. Supplement, Tab. Ill, fig. 17. 



Spec. Char. PL Testa elongato-fusiformi lavi, anfractibus G, convexiusculis ; obsolete 

 angulatis ; suturis distinctis, sub-depressis, spira brevi, apice obtuso, apertura dimidiam 

 aquante ; canali longuiscula, labro simplici acuto. 



Locality. Red Crag, Butley. 



Length, half an inch. 



The specimen figured is the only one that I have seen, and was obtained by myself 

 from Butley. 



It is perfectly smooth and polished ; it resembles in form PL violacea, Migh. and Ad., 

 but my shell has no sculpture, and it appears too perfect to have been abraded ; moreover, 

 that shell is stated to measure -nyths only of an inch in length, whereas my shell is at 

 least -^ths of an inch. I therefore presume it to be distinct, and have given to it a new 

 name. 



Pleurotoma rufa, Mont. Supplement, Tab. VII, fig. 17. 



Localities. Red Crag, Butley ? Fluvio-marine Crag, Thorpe ? Post-glacial, 

 March. 



The specimen figured of this well-known British shell is one of two found by Mr. Harmer 

 in the March Gravel. The species is given by Mr. Bell from the Red Crag of Butley 

 ('Ann. and Mag. Nat. Hist.,' September, 1S70), and in Dr. Woodward's 'Norwich 

 Crag List ' (in ' White's Directory '), from Thorpe, but I have not seen the specimens 

 for either of those occurrences. 



Pleurotoma quadricincta, S. Wood. Supplement, Tab. VII, fig. 11. 



Spec. Char. PL Testa turrita, sub-fusiformi, costata, costis sub-erectis, anfractibus 

 G — 7, converts transversim stratis, striis paucis ; apertura ovata ,- labro intus lavi. 



Locality. Red Crag, Butley. 



Length, •§ ths of an inch. 



The above represents one of two specimens in good preservation which I found in the 

 Red Crag at Butley. The shell somewhat resembles Murex harpula, Broc, but in the 

 description of that species it is distinctly stated as " interstitiis laevigatis/' The ornamen- 

 tation upon the Crag shell is peculiar ; there are four strong, large, spiral lines upon 

 the lower half of the volution (especially visible between the ribs), and the upper portion 

 is covered with very fine spiral striae. My shell has seven volutions, including the 



