1898] Proccedmgs of I) ish Societies. 165 



acid for swelling purposes ; stained next in a watery solution of Hoff- 

 mann's blue, afterwards passed through dilute acid alcohol into weak 

 glycerine, in which it remained for some time, and finally mounted in 

 glycerine jelly, by this treatment only the fine protoplasmic connections 

 and protoplasts remain strongly stained. The protoplasm of the 

 filamentous thallus showed a peculiar tubular vacuolated appearance, a 

 number of tubules lying more or less parallel to one another inside a 

 larger tube, each tubule being apparently filled with droplets. The 

 problem of the structure of protoplasm apart from its constitution must 

 be settled largely by microscopical study. 



Prof. T. Johnson showed a preparation of the spores and elaters of 

 the slime-fungus TricJiia affinis, of which he collected fruiting material in 

 a wood at Howth in December, 1897. The species seems not to have 

 been hitherto recorded from Ireland. 



Mr. H. J. Se^ymour exhibited a specimen of the so-called syenite from 

 Cleopatra's Needle, New York. The piece was originally part of the base 

 of the *' Needle," which was trimmed off to make a flat foundation before 

 being set up. The specimen was kindly lent by Prof. O'Reilly of the 

 Royal College of Science. 



May 19. —Dr. W. Frazkr (President), in the chair, exhibited a series 

 of drawings made from the parasitic growth, Achlya prolifa-a, on gold- 

 fish. They had been origiuall}^ shown several years since, and described 

 by him at the Microscopical Club. They were to illustrate some obser- 

 vations on parasitic diseases in animals. 



Prof. T. Johnson showed a preparation of the hymenium of the 

 dry-rot fungus, Mendius lachymans^ Vx. which had been found growing 

 in the floor of a dining-room in Dublin. Though dry-rot is not un- 

 common in timber the fungus is not often found in fruit. It is closely 

 related to Polyponis, having much shallower tubes lined with a yellowish- 

 brown hymenium. Each basidium carries four sterigmata. Mr. R, J. 

 Moss, F.C.S., stated that recently dry-rot attacked the wood-work of 

 one of the rooms of the R.D.S.'s premises at Ball's Bridge, and cost the 

 Society some ;^2oo. 



IMr. G. PiM showed masses of a Closterium, which occurred in a water- 

 lily pool in his garden. The individuals were exceedingly numerous, 

 forming green patches on the water, and oul}' appeared on the surface in 

 or after bright sunshine. 



Mr. M'Ardi^E exhibited Nostoc sphiericuni, Vauch., which he detected 

 growing in the lobules of Lejcunca flava var. which he collected last year 

 at Tore Waterfall, Killarney. Some specimens of the alga are very 

 minute and resemble the antheridia of the liverwort; more matured 

 specimens swell the lobule very much ; and at length, under such 

 favourable circumstances for its growth, the minute fronds which are 

 enclosed in a colourless periderm grow through the aperture formed by 

 the lobe and lobule of the Lejcunca, and are possibly carried by the 

 current of moisture into the next empty lobule, where they quickly form 

 the minute spherical mass so characteristic of the species. 



