56 



J. H. PRICE, I. TITTLEY & W. D. RICHARDSON 



BRITISH MUSEUM ;N*rutAL His 



Plate 3 A: A Padina-like plant of Taonia from Brighton, collected by Mr Pike in 1854. The colour 

 is more yellowish, the texture peripherally rather more delicate, and the apparent splits more 

 pronounced, than is usually the case with Padina; similarly, the surface of the plant is neither 

 roughened nor slightly whitened. However, on shore, it would be relatively easy Tor an inexperienced 

 observer attempting quick determinations to confuse the two. Compare this with the correctly 

 determined Padina in Plate 3B. Burnett Collection [BMJ. B: Specimens of Padina from approxi- 

 mately the same era as the Taonia of Plate 3A. Note the close resemblance of the lower right and 

 lower left plants on the upper (Isle of Wight; September 1860) clump of Padina to the plant of 

 Taonia illustrated in Plate 3A. Burnett Collection [BM]. 



the above doubtful or unlikely populations or individuals are therefore difficult to dismiss without 

 further consideration. There is only one real possibility of confusion in determination of Padina 

 on British shores. Those with little field experience could find that distinguishing between Padina 

 and Taonia, in some states, could raise problems. The rather flabelliform growth-form of Taonia 

 that sometimes occurs amongst populations on even the south-eastern coasts of England (where 

 Taonia occurs less frequently than is usual elsewhere) could be taken for degenerating specimens 

 (with vertical splits) of Padina pavonica (see Plate 3, A & B). Taonia, although rather more tolerant 

 of exposure to wave-action than appears generally to be true for P. pavonica, is still mostly present 

 in similar conditions to the Padina, sometimes even alongside it. It is not easy to believe, however, 

 that all those experienced workers indicated earlier, recording or discussing occurrence of P. 

 pavonica in the most specific terms, could have made this mistake in observation. 



