PROCEEDINGS OF SOCIETIES. 125 



DUBLIN NATURAL HISTORY SOCIETY. 



MAY 18, 1855. 

 Dr. CHOKER, M.R.I.A., in the Chair. 



After the preliminary business, the Journal of the Geological Society of Dublin, 

 vol. vi., part 2, presented by the Society, was recorded, with other donations. 



The thanks of the Society having been given, Mr. Andrews stated that the paper 

 on the list for this evening, " On the plants in the neighbourhood of Sligo, and on 

 the effects of the severe frost," would be deferred until the next evening, as he had 

 received a communication from the Rigbt Hon. John Wynne, saying that he would 

 be able to give a more accurate account of the effects of the frost by waiting a little, 

 as some plants which, at present appear dead, may grow after the rain. 



Mr. Gilbert Sanders then gave his paper 



ON THE ADVANTAGE TO BOTANY OF LOCAL LISTS, AND NOTES WITH REFERENCE 

 TO THE ALG.E OF THE EAST COAST OF IRELAND. 



As I have not seen a list of marine algee which have been collected from time to 

 time by various algologists in our bay and the neighbouring shores, I am induced 

 to offer a contribution to the formation of a local list ; and I propose that we con- 

 sider Balbriggan as the northern limit, and Wicklow Head the southern boundary, 

 o'' \\hat I would beg leave to term the Dublin district of coast. I have selected 

 these two extreme points, on account of their being favourable places for collecting 

 and being so easily accessible by rail, as are also all the intermediate spots along 

 the line of coast. The eastern shores of Ireland, bordering on the Irish Sea and 

 St. George's Channel, have not been sufficiently explored. There is an impression 

 that these shores are not prolific of species. One of our most eminent algologists 

 said to me, about four years since, that the Dublin shores were not favourable for 

 the study of algology, but I think thai; opinion was incorrect. My friend, Dr. Cocks, 

 of Devonport, spent about two hours at Bray, and a similar time at Howth, in the 

 summer of 1853, and in these two hasty visits he saw upwards of fifty species. 

 Low water, at spring tides, is the most favourable for procuring the rarer speciea 

 and most perfect specimens. The rock-pools, which are only uncovered at spring- 

 tides, are the best spots for searching, these being the favourite habitats of many- 

 scarce algse. To search these pools satisfactorily, we require considerable light, 

 for without it we cannot see to any depth, or even the sides of the submerged rocks 

 under the shelter of which the more delicate filamentous algasgrow. On the south- 

 western shores of England, and the southern, western, and northern shores of 

 Ireland, and all the shores of Scotland, the time of low water spring-tides is from 

 three hours before noon to three hours after, during which there is sufficient 

 light for collecting; but, unfortunately for algology, in our own immediate district, 

 the same state of tide occurs at six or seven o'clock morning and evening; 

 therefore, the examination of pools, at low water springs, can be conducted on our 

 coast only for about three or four months viz., the summer and we are excluded 

 from them altogether during the autumn, winter, and spring, seasons fully as 

 interesting to the algologist as the summer months. The beautiful pencilled tufta 

 of the sporochnacese are only visible in spring, and many algae are not in perfection 

 except in winter. Possibly it may be owing to the unsuitableness of the tides that 

 the Dublin coast has the reputation of being unprolific. We can see, however, in 

 the example before us, what may be done by assiduity, by carefully examining 

 what the waves will bring us, especially after storms. When I was able to devote 

 some time to the sea shore, I found the second or third tide (high water), after 

 the storm ceased, to be the best time for examining the rejectamenta. Marine 

 botany will be much benefitted, if collectors will carefully note every circum- 

 stance connected with the abundance of certain plants in particular spots, or 

 seasons, and likewise the changes they may perceive in the forms. The 

 VOL. II. I 



