250 PROCEEDINGS OF SOCIETIES. 



this interesting subject can be considered as even approaching comple- 

 tion ; of the reproduction of several forms we may be said to know 

 nothing. Were it not for this comparatively backward state of our 

 knowledge, I would not have ventured to bring forward these meagre 

 and incomplete researches. On a future occasion I trust to have the 

 pleasure of laying before you a more full and ample account of the pre- 

 sent state of our knowledge of these strange and beautiful organisms. 



NOTE ON A CURIOUS MONSTROSITY OF THE COMMON SHELL (FUSUS ANTIQUUs).* 

 BY G. C. HYNDMAN, BELFAST. 



PLATE VIII. 



The specimen exhibited was obtained by dredging off Groomsport, in 

 the county of Down, by Mr. Samuel Yance, along with Mr. Murray. 

 Unfortunately, the animal was not preserved, as the shell was boiled along 

 with a number of others before its singular form attracted notice. I have 

 no hesitation, however, in referring to it as a curious and interesting mon- 

 strosity of the Fusus antiquus, although its convolute form more nearly 

 resembles that of the foreign genus, Delphinula. The colour and struc- 

 ture of the shell, together with the projection of two or three turns of 

 the original apex from the centre of the coil, confirm my view, and, no 

 doubt, the abnormal form has been occasioned by some accident befalling 

 the animal whilst in the young state, which obliged it to change the 

 usual angle of the body whorl with the central spire, and thus the shell 

 has become convolute, as we see. 



ON THE EMRYYO STATE OF PALINURUS VULGARIS.* BY R. Q. COUCH, 

 M.R.CS. ENG., ETC. ETC., NORTH PENZANCE. 



PLATE XVII. 



At the time of the publication of Professor Bell's admirable work on 

 British Crustacea, by some inadvertency the particulars respecting the 

 embryo condition of Palinurus vulgaris were overlooked, and up to the 

 present time have not been published. As several years have now 

 passed, and the subject has not hitherto attracted the attention of any 

 other observer, I would wish to publish the following observations : — 



The metamorphoses of the Decapod Crustacea may now be considered 

 as established by observations made in every part of the world. The first 

 announcement of the discovery came from Ireland, from experiments 

 made near Cork by the late J. V. Thompson. 



The form under which the young Decapods first appeared was an- 

 nounced as belonging to the genus Zoea, and all subsequently published 



* Read before Section D at the Meeting of the British Asssociation, Dublin, August 26, 

 1857. 



