DISTRIBUTION OF CERTAIN BRITISH ALG^ 35 



(3-5-4-5 X l'8-2 cm.), and much like those of Sutton Hayes, 703, 

 from Panama. The fii'st Nigerian record for this species. No. 3398. 

 Maprounea vievibranacea Pax & K. Hoffm. Distribution : 

 Cameroons and Spanish Guinea to Belgian Congo ; now first 

 reported as a Nigerian plant. No. 3253. 



Description of Tab. 529. 

 1. Branch with inflorescence, natural size, of Talhoticlla cketciisis Bak. fil. 

 2. Buds with narrow bracteoles, x 2, 3. Flower, x 2. 4. Longitudinal section 

 through flower, x 8. 



THE DISTEIBUTION OF CBETAIN BRITISH ALG^. 

 By a. D. CottoxV, F.L.S. 



When discussing the peculiar features of the marine flora of 

 the West of Ireland in the report for the Clare Island Survey 

 (Trans. Roy. Irish Acad. vol. xxxi.part 15), theoretical conclusions 

 with regard to certain species were hampered owing to lack of 

 precise data as to distribution. This applied not only to the 

 Continental range, but also to that in our own country. Three of 

 the most noteworthy were Ptilota pliiiiiosa, Gallitliamnion arlms- 

 cula, and Codium mucronatum var. atlanticum, each of which 

 possesses a somewhat remarkable distribution in the British Isles. 

 All three were plentiful in the warm waters of the Clare Island 

 district, and they occur also on the west of Scotland, but none of 

 them are found in any part of the English Channel or south-east 

 of England. The difficulty with regard to the English east coast 

 admitted of explanation ; but it was not easy to understand why 

 these plants should not extend by way of the Welsh coast to 

 Devon and Cornwall. 



The algal flora of Wales, from Anglesea to St. David's Head, 

 is but poorly known ; and it was not possible to state in the 

 Report whether the species in question reached this region or 

 whether they stopped short at a point further north. There was 

 also a measure of uncertainty with regard to North Devon and 

 North Cornwall, although this area had been often and thoroughly 

 explored. Unlike some algae, these are conspicuous species and 

 of well defined habitats, so that they could hardly be overlooked 

 if properly searched for. Two trips therefore were made to the 

 Welsh coast during the past season with a view to certifying the 

 presence or absence of these and other species, the districts chosen 

 being Cardigan Bay (Barmouth to Aberystwyth) and Pembroke- 

 shire (Newport Bay to near St. David's Head) ; whilst during a 

 summer holiday at St. Ives some of the north Cornish coast 

 between Padstow and the Land's End was examined. 



The following notes refer only to the species mentioned above. 

 It appears worth while to publish details of the trips instead of a 

 mere statement of results, as the marine botany of Wales has 

 been somewhat neglected. 



We may first recall the distribution of the species in question. 



