The Irish Naiioalist. January, 



DUBLIN MICROSCOPICAL CLUB. 



XuvKMBKR 10. — The Club UR'l at Leinster House. 



A. R. NlCHOl^S (,Vice-Presideul) exhibited the Marine Polyzoon, Lcpralia 

 J'ciiusa, Esp., on a shell o{ Pecloi ina.ximus from Roiindstone, Co. Galway. 

 Although Avidely distributed and found at several places on the English 

 and vScottish coasts, this species appears to be rare on the Irish coast, and 

 has only previously been recorded from off Belfast Lough, 



F. W. Moore showed Uicdo Lyuc/iii, a fungus which is found only on 

 Orchids. It was established on Epidcndriirn viielliniif/i. a ^Mexican Orchid. 

 This species was first noticed growing on a species of Spiranthes from 

 Trinidad, at the Royal Gardens, Kew, in 1885. Since then it has spread 

 to several collections, and this is the second occasion on which it has 

 been found on orchids in the Glasneviu collection. As a rule orchids 

 are particularly free from fungoid pests, probably owing to the thick 

 nature of their epidermis. 



\V. V. GuNX showed sections of the seed coats of B/ass/ta canipcslris 

 CSwede) and />. rapits (Rape). The seeds of these two species of Brassica 

 so closely resemble one another in their external and naked-eye appear- 

 ance, that it is iuq^ossible to determine by this evidence alone to which 

 species a sample of seed should be referred, and it becomes necessary to 

 resort to other means of identification. Since 1871 quite a number of 

 workers, mostly on the Continent and in America, have investigated the 

 histology of the seed coats, and amongst others Schroder, Sempolowski, 

 Wittmack, and Hohnel have published the results of their work, and 

 mere recently A. J. Pieters and V. K. Charles, of the L"^nited States 

 Department of Agriculture, have carried out an exhaustive enquiry. It 

 is now possible to distinguish between a number of the economic species 

 of Brassica such as Cabbage, Black Mustard. Charlock, Turnip, (Sec, by 

 the structure of their seed coats. The differences between Swede and 

 Rape are less marked than in the other species of this genus, but Messrs. 

 Pieters and Charles claim that by special methods of staining and 

 mounting, distinctive characters are obtained which differentiate them 

 from one another. The slides shown, however, which were made by a 

 professional mounter from commercial seed, were not sufiicieutly 

 characteristic to be of practical value for identification, and we are still 

 without a convenient means, suitable for everyday use, of determining 

 these two species. 



X. Coi.GAN exhibited living specimens of the Two-spotted vSucker-fish, 

 f.cpadogasier biiiuiiulalits, and of the Gephyrean worm I'hascclion Sliofiibi, 

 which he dredged in ten fathoms off Dalkey sixteen days previously. 

 The worm, which was lodged in an empty Tooth-shell, DcutaliuDi cntalis, 

 one inch long, was kept in captivity in a deep glass bowl the bottom of 



