114 Rev. A.M. Norman on the Discovery 



In the specimen described^ the cloaca has been torn away from 

 the anal opening by muscular contraction in death, and is lying 

 in the body. A short distance above, is seen an opening in the 

 integument (fig. 4), from whence the cloaca would appear to 

 have been torn. 



The total length of the expanded Echinoderm is 1^ inch, the 

 breadth \ inch. 



Strephenterus claviger was taken in the autuuni of 1858 in 

 Bantry Bay. 



EXPLANATION OF PLATE IX. figs. 1-4. 



Viy. 1. Strephenterus claviger (Norman), slightly enlarged. 



Fig. 2. A tentacle-head magnified, showing, a, the opening into the interior; 

 b and c, supplemental jjrocesses. 



Fig. 3. Another tentacle-head magnified, in which the pear-shaped bodies 

 {d, e,f) are seen within the investing membrane. 



Fig. 4. Internal organs of fore part of body : g, inner tunic ; //, the funnel- 

 formed mouth ; i, the oesophagus ; k, the cloaca of the intestine, 

 which has been torn away from the anal aperture, I. 



Sedgefield, co. Durham, Dec. 31, 1860. 



XVI. — On the Discovery o/Physa acuta [Drup.) in England. 

 By the llev. Alfred Merle Norman, M.A. 



[Plate IX. figs. 5-9.] 



Physa acuta (Draparnaud). 



Fhysa acuta, Drap. Moll. T. et F. France, p. 55, pi. 3. f. 10, 11 ; Brard, 

 Coq. Envir. Paris, p. 169, pi. 7. f- 5, 6; Brown, Illus. L. and F. 

 Conch. Great Britain, pi. 3. f. 9, 10 (copied from Drap.). ; Moquin- 

 Tandon, Hist. Nat. Moll. T. et F. France, vol. ii. p. 452, pi. 32. f. 14- 

 23, and pi. 33. f. 1-10; Michaud, Comp. Drap. Moll. France, pi. 16. 

 f. 19, 20.* 



IBulla rivalis, Mat. and Rack. Trans. Linn. Soc. vol. viii. p. 126, pi. 4. f. 2 ; 

 Mont. Test. Brit. Supp. p. 97. 



1 Physa rivalis, Turton, Man. L. and F. Shells, p. 128. f. 112 (copied from 

 Mat. and Rack.). 



Animal pinkish ash- colour, thickly sprinkled on all parts of 

 the upper surface with black specks, those on the head being 

 largest. Head bilobed in front and slightljr expanded. Ten- 

 tacles a little thickened towards their apices, and remarkable for 

 having a black central line. Foot short, only reaching to the 

 suture that divides the second from the third whorl, neither 

 carinated nor acutely pointed behind. Mantle-edge bounded by 

 the margins of the aperture of the shell, and not at all reflected 



* The references given are only to those works that I have had an 

 opportunity of consulting. For additional synonyms see Moquin-Tandon 

 and ' The British MoUusca,' vol. iv. p. 146. 



