1897.] CoLGAN. — On the Flora of the Shores of Lough Derg. 19I 



Inishparran Point. On the seventh day, July 30th, Killaloe 

 was reached by rowing-boat from Mount Shannon, and on the 

 way down the lake numerous landings were made, as at 

 Rineacrush Point, the Lushag Rocks, Scilly Island, Bull 

 Island, and Cormorant Island, all on the east shore and in Co. 

 Clare. Finally, on the eighth day, July 31st, before leaving 

 Killaloe by the mid-day train, a fl3dng ascent was made of 

 Glounagalliagh mountain, 1,746 feet in height, and lying two 

 miles inland from the lake shore, and four miles north-west of 

 Killaloe. 



Altogether, some 20 islets and 12 points or promontories 

 along the lake shores were rather carefully examined, and as 

 a result of the week's exploration 403 species were observed, 

 or 408 including Characese. Considering the large area 

 traversed this number may seem disappointingly small; but 

 it must be borne in mind that in only one instance were the 

 observ'ations pushed inland for more than a mile or carried 

 upwards for more than 50 feet above the lake-level, that fully 

 half of the working hours were spent on the water and were 

 comparatively barren of results, and that the season was so far 

 advanced that many of the plants of spring and early summer 

 were overlooked. A comparison of my notes with the detailed 

 reports on the I^ough Erne flora b}^ Mr. R. M. Barrington^ and 

 on the Lough Ree flora by Messrs. Barrington and Vowell,"^ 

 seems to justify the conclusion that the Lough Derg flora if 

 more fully investigated would prove by so much richer than 

 that of lyough Erne as it would prove poorer than that of 

 Lough Ree. Three weeks on Lough Erne, divided between 

 the months of August, 1881, and June, 1882, yielded 417 species 

 to Mr. Barrington, a fortnight on Lough Ree in June, 1885, 

 and August, 1886, gave Messrs. Barrington and Vowell 481 

 species, and as the shores of all three lakes are preponderantly 

 limestone, and the areas examined are not glaringly unequal, 

 the floras admit of fair comparison. 



Roughly speaking, the northern two-thirds of the Lough 

 Derg shores are calcareous, the southern third non-calcareous, 

 and the change of flora with change of rock was very strikingly 

 shown on touching at Freagh wood when running west from 



• On the Flora of the Shores of Lough Erne ; Proc. R.I. A., 1884. 

 2 On the Flora of the Shores of Lough Ree; Proc. KI.A., 18S7. 



