60 Royal Irish Academy. 



fitaminibus longe exsertis, antheris filamentis siinplicibus 6 plo brevi- 

 oribus. 

 5. /. indicus, triandrus ; capit ulis multifloris squarrosis trichotome cy- 

 mosis, sepalis lineari-lanceolatis apice mucronatis recurvis capsulae mu- 

 ticse longitudiiie, stigmatibus sessilibus. 



ROYAL IRISH ACADEMY. 



December 10. — Sir W. R. Hamilton, A.M., President, in the Chair. 



Mr. Ball read a paper, entitled " Description of the Cydippe po- 

 miformis, Patterson, {Beroe ovatus, Flem.,) with notice of an ap- 

 parently undescribed species of Bolina, also found on the coast of 

 Ireland." By Robert Patterson, Esq., Member of the Natural 

 History Society of Belfast. 



The author referred to a paper of his published in the * Edinburgh 

 New Philosophical Journal' for January 1836, giving some account of 

 a tentaculated Beroe taken in abundance by him at Lame Lough, 

 County of Antrim, in the spring of 1835. He then noticed the occur- 

 rence on different occasions in 1 83 6-7, of a Beroe, exhibiting a peculiar 

 ramiform arrangement of whitish internal vessels, branching off from 

 near the lower part of the stomach to the several bands of cilia ; and 

 detailed the observations by which he was enabled to identify this 

 with the BeriJe described in * Mem. Wer. Soc.,' vol. iii. p. 400, by 

 Fleming, — the tentacula having escaped the notice of that writer 

 from the specimen he examined having been in an exhausted state 

 when these organs were retracted within the body. The presence 

 of the tentacula removes the animal from the genus Beroe of Fleming, 

 to the Pleurohrachia of the same author {Cydippe Eschs.) and as the 

 specific name ovata, under which it was described in the * Hist, of 

 Brit. Animals,' has been applied to a different species, Mr. Patterson 

 proposed that it should be designated as the Cydippe pomiformis. 



The disappearance of the internal ramiform vessels was next no- 

 ticed, and the steps by which the writer was enabled to ascertain 

 that the species now brought forward was identical with that de- 

 scribed by him in 1 835 ; and consequently, that a Beroe, of the oc- 

 currence of which we have no record, except of one individual taken 

 in 18*20, was abundant on the Irish coast. Particular reference was 

 made to Dr. Grant's paper, 'Zool. Trans.' vol. i. p. 9, on B.pileus, 

 with a view to indicate the several points of agreement and of dif- 

 ference between these, the only two British species of tentaculated 

 Beroes. The structure of the cilia, the aqueous currents at their 

 base, the position and structure of the tentacula, the food of the 

 Beroe, its vitality, consistency, want of phosphorescence, movements. 



