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PROCEEDINGS OF IRISH SOCIETIES. 



RoYAiv Zooi^oGiCAi, Society. 



Recent donations include a Cormorant from Captain Boxer ; a Golden 

 Pheasant, a Ringed-necked Pheasant, and a number of fish from F. 

 Godden, Esq. ; a pair of Canadian Geese, and a Reeve Pheasant from 

 Sir Douglas Brooke ; and a pair of Wood Pigeons from K. M. Dunlop, 

 Esq. A large Mandrill, a Chilian Sea Eagle, and two Turkey Vultures 

 have been purchased. 



10,350 persons visited the Gardens in October. 



Dubinin Microscopicai, Club. 



October 17th.— The Club met at Dr. R. F. Scharff'S. 



Prof. Coi,E exhibited the petrological microscope elaborated by 

 Mr. Dick in conjunction with Messrs. Swift and Son, of London, an 

 example of which has been purchased for the Geological Laboratory of 

 the Royal College of Science for Ireland. The main feature of the 

 instrument is the rack-and-pinion arrangement, whereby the polariser 

 and analyser can be rotated together or separately while the stage 

 remains fixed. In the older instruments where the stage was rotated 

 between the nicols, there was great difficulty in keeping the centering 

 sufficiently accurate to retain the object in the field when high powers 

 were employed. 



Mr. Greenwood Pim showed a curious Sphccria, found on rotten wood 

 in considerable abundance at Brackenstown, Co. Dublin, a few weeks 

 previously. It was densely bearded with short white hairs; the peri- 

 thecia under a low power resembling some furry animal. The asci 

 could be distinctly traced, but the sporidia were not fully developed, so 

 that the identity of the species was a matter of some doubt. It will 

 probably prove to be S. canesccns. 



Prof. Johnson showed Aglaozonia reptans, Kiitz., a brown alga growing 

 on the calcareous red alga, Litkothaninion calcareum, and obtained by 

 dred^ng in Roundstone Bay in September, 1893. This is the only Irish 

 locality given in Harvey's *' Ph3'Cologia Britannica." The exhibitor 

 has this year got it in the S.W. of Ireland, on Lithothamnion agariciforme, 

 itself an addition to the S.W. A section showing the unilocular 

 sporangia (asexual) was exhibited. The species is well worth a detailed 

 study at the sea-shore, as it is, in all probability, as Reinke first suggested, 

 the asexual creeping generation of a species of which Cutleria multijida is 

 the sexual erect generation. 



Mr. H. H. Dixon showed preparations of the pollen mother-cells of 

 Lilium longiflortan. Before entering on the early stages of karyokinesis the 

 nucleus of these cells possesses a very delicate and complexly coiled 

 nuclear thread. Portions of this thread lie parallel to one another, and in 

 some places these portions present the appearance of a single thread 

 which has undergone longitudinal fission. That this is not the case, 

 however, appears probable from the sudden divarications of these portions 

 from one another and the way in which they often lie across one another, 

 and also from the fact that in later stages the divarications are not so 

 conspicuous. As the thread thickens the parallel portions become more 

 regular in their disposition and finally transverse fission divides it into 

 a number of chromosomes, each composed of two parts lying more or 

 less exactly parallel to one another. Sometimes the two portions of a 

 chromosome form a loop which is possibly derived from a loop in the 

 original thread, and sometimes they are twisted on one another. Thus it 

 appears probable that the doubling of the chromosomes before the for- 

 mation of the nuclear plate is in this case not due to longitudinal fission 

 of the thread, but to lateral approximation of two portions of it. 



