1897-] Proceedings of Irish Societies. 47 



Dubinin Microscopical Club. 



November 19.— The Club met at the house of Mr. G. H. Carpenter, 

 who showed specimens of the larva of the dipteron Sivmlhimy taken at 

 Carton, Maynooth. These highly interesting aquatic larvae are fully 

 described by Prof. Miall in his recent book on the " Natural History of 

 Aquatic Insects." Fastened by a sucker at the hinder end of the body, 

 they set up currents in the water and sweep food into their mouths by 

 means of a pair of processes with long fringes situated on the head. 



Prof. T. Johnson showed a preparation of a microscopic green disc- 

 like alga, Pringsheimia scutata, Rke., which is found as an epiphyte on 

 Polysiphonia, Zostera, and other marine plants. It is closely related to 

 Mycoidea parp,siticay which causes a coffee disease, and to Phycopdtis, of 

 ■which Mr. Jennings recently described two new species before the 

 Royal Irish Academy. P. scutata was added to the list of Irish marine 

 algae on the B.N.F.C. dredging excursion in July last in Belfast Bay, and 

 is recorded by Miss Hensman and the writer in the Irish Naturalist for 

 October, 1896. 



Mr. Greenwood Pim showed a remarkable mould parasitic on leaves 

 of Rape, sent him by Rev. Canon Russell from near Tullamore. 

 It belongs to the genus Ramidaria. Mr. Massee of Kew, to whom 

 specimens were submitted, writes that he had no hesitation in stating 

 it to be a typical Ramidaria — but undescribed specifically. It is intended 

 to publish a description of it in an early number of the Journal of Botany, 

 under the name of Ravmlaria rapce. 



Mr. McArdlE exhibited a specimen oi Lepidozia setacea, Web. (Lindberg), 

 bearing perianths on short lateral branches. The plant, though widely 

 distributed in Ireland, is remarkable in the form of its leaves, which are 

 transversely placed on the stem and divided into two or three setaceous 

 segments, incurved and jointed by transverse septa ; those near the 

 apex of a shoot become nearly verticillate, which gives the plant a 

 remarkable appearance ; in this way it approaches closely one other 

 lyiverwort, Blepharostoma trichophylla, Linn. (Dumort). Sir Wm. Hooker 

 states in his " British Jungermanise " that the resemblance of these two 

 plants when under the microscope to Conferva 'yerticillata is worthy of 

 remark. 



Mr. R. J. Mitchell showed several photo-micrographs of sections of 

 rocks and plant-stems. 



Rev. Canon Russell exhibited the wing of a Chalcid-fly, and called 

 attention to four rings set in the fork of the stigma in which an offshoot 

 from the subcostal vein terminates. These discs, so far as he can learn, 

 have not been noticed heretofore. A fine nerve was observed passing 

 near or through one or more of these rings, which the exhibitor believes 

 may be traced all along the subcostal vein, to a row (or rows) of oval or 

 round vesicles at the base of the wing, closely resembling the so-called 

 otoconia or otoliths found in the halteres of the diptera. Mr. Russell 

 showed a sketch from the pen of a correspondent of a balancer of 

 Sarcophaga carnaria, in which a similar arrangement is apparent, 



