EICKMAN — ON CYRENA DULWICHIENSIS. 



211 



a narrow, npriglit, ribbon-like band, pressed against the preceding 

 whorl, and feebly crennlated by the lines of growth ; in well 

 preserved specimens the margin, immediately in front of the 

 sutural band, presents two or three obscure concentric furrows. The 

 last whorl is somewhat attenuated towards the base ; the aperture 

 is entire, rounded in front, narrow behind, and very long, nearly 

 equalling four-fifths of the entire length of the shell ; the columella 

 is obscurely and very obliquely twisted, and anteriorly is much 

 curved ; the outer lip is slightly arched, simple, and sharp on the 

 edge ; the inner lip is posteriorly thickened and narrow, anteriorly 

 efiuse, flattened, and reflexed, forming an angular ridge on the colu- 

 mella, and confluent with the outer lip. 



8ize. — The dimensions of my largest specimen, if it were perfect, 

 would be, Axis, 2 inches and 2-12ths nearly ; Diameter, 1 inch. 



Explanation of Plate V. 



PiTHAEELLA EicKMANi. — Fig, 1. — Front View. Fig. 2. — Back Yiew. Fig. 3. — 

 Portion of Pytharella, showing twist in the columella. From specimens in, 

 the collection of F. E. Edwards, Esq., to whose liberality we are indebted for 

 this plate. 



intotice aot) description of GYEENA DULWIGH- 



lENSIS. 



By Charles Hickman, Esq., Hon. Curator of Lambeth Museum. 



In a former communication to the " Geologist," treating of the 

 fossil fauna and flora observed in Lower Eocene strata passed 

 through at Dulwich and Peckham, in the construction of the Great 

 South High Level Sewer, I mentioned the fact of having discovered 

 in a shelly conglomerate at Dulwich, a new species of the estuarine 

 genus Cyrena, which I proposed to call Cyrena Dulwichiensis. In 

 sinking the main shaft, at a depth of fifty to sixty feet, this con- 

 glomerate occurred in nodular masses in green shelly sand, inter- 

 calated with wedge-like bands of stiiF black clay, highly charged 



