ZOOLOGICAL AND BOTANICAL ASSOCIATION. 151 



To these may be added a fifth species, first discovered by the author 

 in Dublin Bay, and since found by him on several parts of the south- 

 west coast of Ireland. The umbrella of this Equorea varies in shape, 

 being in some specimens almost discoidal, whilst in others it is campa- 

 nulato and convex. The sub-umbrella is about half the height of the 

 disk. The central polype is exceedingly simple in structure, apparently 

 consisting of two regions, from the upper of which issue the gastro-vas- 

 cular canals, which vary in number from eight to twelve, according to 

 the size and age of the specimens selected for examination. The marginal 

 tentacles are very numerous, and highly contractile, each springing from 

 a pale tawny bulb, at the upper part of which is situated a conspicuous 

 ocellus, of a black, or rather, perhaps, intensely dark violet, colour. To 

 the naked eye these ocelli are invisible, but they serve to impart an ex- 

 quisite roseate tinge to the margin of the disk. The reproductive glands 

 occur as thickenings in the radiating canals, being usually placed in the 

 neighbourhood of the central polype. It is probable that this Equorea 

 is identical with some one of the numerous foreign species of the genus 

 described by Peron, or Quoy and Gaimard ; but the descriptions given by 

 these authors, too often scanty and insufficient, together with the im- 

 possibility of obtaining access to the plates of Peron and Lesieur, renders 

 this point difficult of determination. This Medusa is gregarious, occur- 

 ring in considerable numbers in those localities where its presence has 

 hitherto been detected. In size it does not exceed one inch in diameter. 



Dr. Kinahan read the following communication : — 



DESCRIPTION OF PANDALUS JEFFREYSII (SPENCE BATE, " FAUNA OF SWANSEA," 

 I860). BY C. SPENCE BATE, F.L. S., CORRESPONDING MEMBER. 



Pandalu8 Jeffrey sii (Sp. Bate). 



P. rostro recto, superne pauce-dentato (7-8), infra binis dentibus, 

 apice vicino, armatis. 



Jeffrey' 8 JEsoj> y Prawn. 



Rostrum not turned up at the extremity, armed above with eight 

 teeth, the two posterior being separated by a space from the others, and 

 two below not remote from apex. 



This animal in general form approximates to the Hippolytes. The 

 rostrum is shorter than in Pandalus annul icornis, and directed in a straight 

 line. Five of the six anterior teeth thnt surmount the rostrum are an- 



ZOOL. & BOT. SOC. TROC. — VOL. I. Y 



