Mr Patterson on a Species ofBeroe. 9ft 



by means of the ferry-boats, an easy mode of taking, at all hours 

 during the day, the small MeduscB and Crustacea^ which the flow 

 of the tide placed within reach of a small canvass towing net. As 

 the Beroes could thus with facility be procured, and were to me 

 highly attractive, my sitting-room, for between two and three 

 weeks, was never without some of them. They were kept in 

 glass jars, the water in which was changed twice each day. 

 With this precaution only, a few individuals were kept alive and 

 vigorous for five days, and might with similar care have conti- 

 nued so for a much longer period. In general, however, after 

 a few hours' confinement, or at most after a couple of days, they 

 were poured back into the sea, and their place supplied by other 

 individuals. In this way I had a constant succession of beroes 

 newly taken, possessing in perfection their locomotive powers, 

 and forming a subject for ceaseless admiration and remark. 



The size of the animal is from two to seven lines in length, and 

 about one-third less in breadth, exhibiting a regular oval form. 

 Many individuals are, however, globose, or more nearly resem- 

 bling the shape of an orange. In every other respect they ap- 

 pear alike, and I attribute the difference rather to a contractile 

 power possessed by the animal, than to any permanent dissimi- 

 larity in form. The body is transparent and colourless, with 

 the exception of a deep coloured conspicuous pink line towards 

 the centre of the stomach, which line becomes bifurcate asit ad- 

 vances upwards. 



It is furnished with eight bands placed at regular intervals, 

 and extending at each side about three-fourths of the distance 

 from the mouth to the anus, but approaching more nearly to the 

 latter. To these bands the cilia are attached, and, as the band 

 is less broad at either extremity than in the centre, the cilia ex- 

 hibit a corresponding decrease. Dr Grant, in speaking of the 

 cilia of B. pileics, states, that there are about forty in each band, 

 and that " they are not single fibres, but consist of several short 

 straight transparent filaments, placed parallel to each other in a 

 single row, and connected together by the skin of the animal, 

 like the rays supporting the skin of a fish."" In the Irisii species 

 of beroe now under consideration, the number of cilia is much 

 less than is here stated. In some individuals they amounted to 

 only fifteen, and in none did they exceed twenty-seven. The 



