DUBLIN MICROSCOPICAL CLUB. 213 



Zygospore of Micrasterias papilliferd, for the first time found in 

 Ireland. — Mr. Archer showed the zygospore of Micrasterias papil- 

 lifera, Breb. from Griencolurabkille, Co. Donegal. This rather common 

 species, though not at all abundant, does not seem to have been 

 met with conjugated since recorded by Ealfs. As is shown by that 

 author, the zygospore is very like, though, of course, smaller than 

 that of Micrasterias denticulata, Breb., though the mature plant is 

 quite dissimilar, and it is seemingly of interest to note this fact, 

 seeing the very dissimilar zygospores of the latter and that of M. 

 rotata, Ralfs, although these two forms, from possessing a con- 

 siderable resemblance to one another, have ere now by some been 

 held to be but varieties one of the other. The present examples 

 formed exceedingly ornate objects. 



New Species of Colpocephalum, exhibited. — Mr. H. W. Mac- 

 kintosh showed a new species of Colpocephalum from Ardea 

 purpurea, of which he would, ere long, prepare a figure and due 

 description ; its nearest ally was C. jlavescens. — Dr. Macalister 

 showed, as further illustrative of the genus and for sake of com- 

 parison, Colpocephalum zebra. 



20th November, 1873. 



Cosmarium Solmiense, /3 Lundell, exhibited. — Mr. Crowe 

 showed a Cosmarium taken by him, in company with Dr. J. Barker, 

 from a wet rock at the Falls of the Rhine, which turned out to be 

 identical with Cosmarium Solmiense, /3 Lundell ; this form has 

 now been taken in Norway and Spitzbergen. 



Sections from a puzzling Fern-liJce stem — a marine waif — ex- 

 hibited, — Mr. Mackintosh showed sections made by him from 

 a stem of fern-like or lycopod aspect, found cast ashore on 

 the Kerry coast, and forwarded by Rev. M. H. Close ; this was 

 about nine inches long, about an inch in diameter, twice dichoto- 

 mously branched, and densely covered in an imbricated manner by 

 the scale-like bases of former leaves, the whole of a black colour. 

 These sections showed scalariform vessels. The origin of this 

 curious waif was quite unknown, the general opinion being that it 

 was of fern nature. 



Action of Chloroform on Hair affected by Porrigo decalvans. — 

 Dr. Frazer showed the action of chloroform in bleaching hairs 

 affected with Porrigo decalvans or true ring-worm, a reaction lately 

 discovered by Dr. Dyce Duckworth. Under this reagent the 

 diseased hairs and portions of the epithelium affected become of 

 pale yellowish-white colour, and an excellent criterion is afforded of 

 the extent of the disease. 



Sections of Nail and Walrus Tooth, exhibited. — Mr. Pearsall 

 showed with the polariscope sections of human nail and of walrus 

 tooth. 



Micrasterias furcata, found for the first time in Ireland, ex- 

 hibited along with M. radiosa. — Mr. Archer showed two very rare 

 forms (as Irish) of Micrasterias, from Co. Galway, viz. Mi- 

 crasterias furcata (Ag.) and M. radiosa (Ag.). The former 



