THE DISTRIBUTION OF PADINA PAVONICA 33 



peripheries of the apparent distribution have been involved (Netherlands and Belgium), or where 

 critical inconsistencies seemed to be emerging, analysis has been as detailed as for Britain. There 

 is locally an absence of modern data very similar to that noted for parts of the British coasts; the 

 parallel extends to a similar distribution pattern where data are available (Fig. 1). 



Benelux 



Drift material sometimes occurs in Belgium and the Netherlands, despite the usual disintegration 

 of plants in situ. If reports can be accepted, this was the source of the record in virtually every 

 occurrence of Padina along Dutch and Belgian coasts. Apart from that, tracing back through 

 records and specimens reveals a very small number of authenticated primary observations of even 

 drift material. The Belgian pattern of records (see following section) is thus essentially similar to 

 the Dutch. There are no naturally rocky or firm substrata along the coasts of the Netherlands and 

 Belgium; sand is predominant, with strong intermixtures of mud in, e.g., the estuary of the Scheldt, 

 where river debris are significant. Den Hartog (1959) emphasises the great importance of artificial 

 substrata in the benthic marine ecology of the Netherlands, and Belgium, although less complex 

 because shorter, has an essentially identical situation. There are a few cases in which detritus over 

 firm artificial substrata exists or existed in the Netherlands, e.g., the Scheldt and parts of the 

 Grevelingen, now sealed against the sea. Nienhuis (1968, 1969, 1970, 1972) made detailed long- 

 term studies of such areas, but never detected Padina; by contrast Boddeke (1957, see below) 

 reported the alga from the Oosterschelde. 



Netherlands 



Oosterschelde : 



Boddeke (1957) '. . . Padina pavonia en Taonia atomaria slechts enkele malen gevonden zijn.' 

 [=were found only a few times.] Record repeated in Dresscher (1976). 



Scheveningen : 



Gorter (1781), '. . . Te Scheveningen aan't Strand. (MEERBURGH) . . .' (as Uha pavonia). 

 Secondary (drift: Scheveningen) records based only on Gorter are: 



Houttuyn (1783); van den Bosch (1853); Suringar (1870; possibly unjustly regarded as wholly 

 secondary); van Goor (1923); Bremer (1943); Lucas (1950). 



Netherlands general: 



Bosch (1851). Record repeated in Dresscher (1976). 



Den Hartog (1959), plant '. . . of southern origin that . . . [is] . . . washed ashore on the coast 

 of the Netherlands . . .'. (Not clear whether this is supported from his own, or entirely dependent on 

 previous, data.) 



The only certainly original Scheveningen record is that in Gorter (1781). The Meerburgh 

 whom Gorter (p. 318) credited with the collection was apparently (p. iv) then the first gardener in 

 the Leiden University Garden. He collected many rare plants in the Netherlands, all being passed 

 to Gorter. Padina was presumably drift, from the phraseology employed; subsequent authors have 

 concluded so. Houttuyn's report, not acknowledged as from the same source, is so close in time, 

 phraseology, and localisation that it must surely be at least largely a secondary reference. Neither 

 can be confirmed from material, and no additional original unpublished data have been traced. 

 There are no specimens of Padina from Dutch European shores in the Leiden collections. This 

 fact also leaves reservations about the record from the Oosterschelde, since the statements by 

 Boddeke lack precision; however, appropriate habitat conditions were hitherto available in the 

 area concerned (see above). 



Belgium 



Oostende : 



Kickx & Kickx (1867), attached to stones thrown up on the beach and on parts of piles tidally 



