118 PROCEEDINGS OF SOCIETIES. 



meeting, and he exhibited an American objective of ^ij power 

 constructed for use on the immersion principle or otherwise. 



Mr. HiSLOP read a paper entitled " Some Suggestions on Oblique 

 Illumination." 



Mr. Draper read a paper " On the Proper Application of the 

 Microscope by Amateurs." 



Three members were elected. 



March ISth, 1868. 



The annual conversazione was given at University College, 

 under the presidency of Mr. Durham, when the entire suite of 

 rooms, comprising the noble library, Flaxman Hall, Shield Eoom, 

 museum, and a dark room for the exhibition of the oxyhydrogen 

 lantern was thrown open, and a numerous company of members 

 and their friends assembled on the occasion. 



Various objects of interest were exhibited by the members. 

 They were well supported by the leading opticians, who vied with 

 each other in the introduction of attractive novelties. Some 

 beautifully-executed pliotographs, a large collection of diagrams, 

 electric apparatus, fish-hatching contrivances, micro-specti^oscopes, 

 stereoscopes, &c., greatly promoted the success of the evening. 



DuBLiK Microscopical Club. 

 17th October, 1867. 



Mb. Abchek desired to record and to exhibit some examples of 

 the zygospore of Closterium costatum (Corda) for the first time seen 

 conjugated. The zygospore, as for this form might be aj^rm^i pre- 

 dicated, is large, broadly elliptic, smooth, and placed between the 

 for some time persistent, empty parent-cells, quite like the similar 

 condition of Closterium striolatum. 



Mr. Archer likewise showed a Closterium new to this country, 

 Closterium cynthia (De Notaris), if, indeed, he were right in the 

 identification, which, without original authentic specimens, is, of 

 course, open to some amount of uncertainty ; yet at the same time, 

 in the present instance, he did not feel much doubt. This species 

 has only just been published by De Notaris in his ' Elementi per lo 

 Studio delle Desmidiacee Italiche ' (p. 65, tab. vii, fig. 71), and it 

 is well distinguished amongst the much curved forms by the cell- 

 wall being striolate, not smooth. It is, moreover, marked by 

 having but a solitary, somewhat large granule in the middle of the 

 terminal space, not a cluster of minute ones. It at once catches 

 the eye by its peculiar curvature, differing from that of the much 

 curved forms at all liable to be mistaken for it ; it is not so equally 

 arched, and the ends are more rounded and blunt than in them; 

 in fact, it is not so graceful a form as C. Leihleinii or C. Diance, 

 which it seems most to approach in size ; it comes nearest C. Jenneri 

 in outline, but is a good deal larger. But from all these, as before 

 mentioned, it diff'ers in being striolate, not destitute of markings. 

 Along with these specimens occurred a variety of other Closteria, 



