AECHEE — ON A NEW SPECIES OF ETJLBOCILZETE, AGARDH. 9 



carclui abounded in such vast number, as, apparently about Dublin, to 

 supersede the common white cabbage butterflies. Early in October 

 last, while standing on the bridge near Lord Bantry's cottage, at Glen- 

 gariff, he had counted some thirty specimens of the latter, and some 

 twenty specimens of the former butterfly, all resting at the same moment 

 on the ivy which grows so luxuriantly over the battlement of the bridge ; 

 and a few days earlier he had seen in the demesne at Muckross Abbey the 

 Colias edusa sporting in numbers over the blackberry bushes. He 

 trusted the result of collections during the past season would increase 

 somewhat the catalogue of Irish Lepidoptera which Mr. E. Birchall 

 was preparing, in conjunction with Mr. Barrett, for the press; and he 

 hoped this catalogue, the extreme value of which no one could doubt, 

 would yet be secured for the Journal of this Society. 



Mr. A. G. More, F. L. S., remarked, as regards the occurrence of 

 Colias edusa in the Isle of Wight, that it was met with in great profu- 

 sion in some seasons, and again, perhaps, exceedingly rarely, or not seen, 

 for half a dozen seasons. Some persons thought that it seemed to 

 make its appearance only once in seven years — others, once in three 

 years ; but, when it did occur, it was, as mentioned by Dr. "Wright, 

 abundant. 



Mr. Williams had seen a specimen of this butterfly in the year 1858 so 

 near Dublin as at his place at Clontarf, but he did not succeed in cap- 

 turing it. The following is the extract from his note book : — " Mon- 

 day, 20th of September, 1858, at Glaslinn, Clontarf; saw a male 

 Colias edusa, but could not catch it for want of a net ; weather here 

 very dry, very little water in rivers; heavy floods in county Kerry." 

 He mentioned that some time ago he had been experimenting in the 

 rearing of caterpillars, particularly of moths ; and he had remarked that 

 the ground colour, though not the markings, seemed to be influenced 

 by the quality of the food supplied to them, but that he seldom suc- 

 ceeded in bringing his specimens in this respect up to the tints of 

 nature. 



Afterwards was read the following paper : — 



Description of a New Species of Bulbociuete, Agaedh. By William 



Aechee. 



The minute little plant which I venture to-night to bring forward 

 and describe belongs to (Edogoniese, a very interesting family of Chlo- 

 rophyllaceous Algae, as yet, however, containing but two genera, but 

 these rich in individual forms. They are, indeed, mainly but simple 

 filamentous plants — that is, composed of cells following one another in 

 a simple branched or unbranched linear series — and casually viewed, 

 perhaps, might be thought attractive only on account of their refresh- 

 ingly bright green colour. But yet these comparatively humble plants, 

 upon a more careful study, present complexities of structure and re- 

 vol. v. c 



