290 Mr. D. M'Kichan on the Number of Electrostatic [May 15, 



III. Genus Histiodeema, Kinahan. 



7. Histioderma hibemicum, Kinalian. 



IV. Genus Planolites, Nicholson. 



8. Planolites vulgaris, Nicholson. 



9. granosus, Nicholson. 



10. articulatus, Nicholson. 



B, Trails.' 

 V. Genus Ceossopodia, M'Coy. 



11. Crossopodia scotica, M'Coy. 



12. lata, M l Coy. 



VI. Genus Nemeetites, M'Leay. 



13. Nemertites Ollivantii, Murchison. 



14. (Palseochorda) major, M'Coy. 



15. (Palaeochorda) minor, M l Goy. 



VII. Genus Myeianites, M'Leay. 



16. Myrianites tenuis, M'Coy. 



17. ■ Murchisoni, Emmons. 



C. Appendix. 

 VIII. Genus Caeldolites, Nicholson. 



18. Caridolites Wilsoni, Nicholson. 



May 15, 1873. 



WILLIAM SPOTTISWOODE, M.A., Treasurer and Vice- 

 President, in the Chair. 



Major Thomas George Montgomerie, R.E., was admitted into the 

 Society. 



The following communications were read : — 



I. " Determination of the Number of Electrostatic Units in the 

 Electromagnetic L T nit made in the Physical Laboratory of 

 Glasgow University By Dugald M'Kichan, M.A. Com- 

 municated by Sir William Thomson, E.R.S. &c. Received 

 April 15, 1873. 



(Abstract.) 



The object of this paper is to describe experiments made at intervals 

 from 1870 to 1872 in the Physical Laboratory of Glasgow University to 

 determine the relation between the fundamental units in the two systems 

 of absolute electrical measurement, the electromagnetic and the electro- 

 static. A summary is also given of the results of similar observations 

 made by W. E. King in 1867 and 1S68. 



