1896. Pro ccedmgs of Irish Societies, 313 



known, measuring only one mm. in length. In structure it is remark- 

 able by the great convexity of the sternum. The palp of the female 

 bears a claw ; this character separates it from the Erigonincc, according to 

 Rev. O. P. Cambridge its true position is near Phokomma. 



Dr. McWeEnEY showed the germinated sclerotia oi Peziza sderotiorum, 

 also known as P. postuma (Berk.). This lives parasitically on potatoes in 

 Ireland, especially along the Western seaboard, and causes a dangerous 

 disease. The sclerotia were gathered in full germination in Co. Donegal 

 last July. He also showed sclerotia artificially produced from the 

 ascospores of the Peziza by planting them on sterilised half cylinders 

 of potato in test-tubes. Reference was also made to a smaller, more 

 adherent form of sclerotium, resembling mouse's excrement, also found 

 on the plants affected by P. sclerotiorum. This smaller form did not 

 produce a Peziza — only a conidial fruitification known as Bot>ytis. 

 The potatoes suffering from Peziza disease were generally affected 

 w^ith Botrytis disease also; but there appeared to be no essential con- 

 nection between the two maladies. 



Mr. A. Vaughan Jennings showed preparations of the peach-coloured 

 Bacterium, Chromatiiun Okenii. This form is specially interestino- on 

 account of its large size, its distinctive colouring, and its habit of living 

 in water containing sulphuretted hydrogen. Sulphur is liberated by the 

 organism, and deposited in granules in the protoplasm, and the sulphur- 

 etted hydrogen is regarded as due to its power of breaking up the sul- 

 phates of lime and soda in solution . Apart from this physiological 

 interest, the form is of value as illustrating the pleomorphism of the 

 Schizomycetes. The motile flagellate type which, nearly half a century 

 ago was named by Ehrenberg Monas Okenii^ is only a stage in a varied 

 life-history. Other stages are the ' sperillum ' form known as Oj>hido??ionas 

 sanguineum, the filamentous form Beggiatoa roseo-persiciiia, and the aggre- 

 gations of 'cocci' constituting the Clathrocystis roseo-persicimis of Cohn. 

 The 'coccus' condition has been described as arising from the fila- 

 mentous form ; but the specimens exhibited indicate that after the 

 motile forms have passed into the 'zooglaea' stage, they too may break up 

 into aggregates of cocci like simple forms of " Clathorcysiisy 



Dr. C. Herbert Hurst showed a section of the cochlea of a Rabbit. 

 Prof. A. C. Haddon showed the Phyllosoma larva of the crustacean 

 Scyllartis arctus. 



Bei^fast Naturai^ists' FieivD Ci,ub. 

 October 27. — The winter session was inaugurated by a social meeting 

 in the Exhibition Hall. The company was a large one, filling the available 

 space in the main hall, and comprising a good representation of the mem- 

 bership of the Club, with many friends. There was an mteresting exhibition 

 arranged in the hall, comprising botanical, conchological, geological, and 

 entomological collections ; photographs^ seals, and microscopic specimens. 

 In the minor hall displays of the X-rays were given by \V. J. Walker. The 

 side hall was devoted to the lantern exhibition of a series of slides depicting 



