14 



date. But the evidence that the Ornithorhyiichus was 

 oviparous was so inconclusive that these two eggs seem to 

 have attracted less attention than they even then deserved, 

 and their apparent disappearance from the collections of 

 the Natural History Society, now in the Owens College, 

 is the more to be regretted since Mr. Caldwell's discovery 

 makes it certain that these missing specimens were what 

 their label declared them to be, viz., the Eggs of the Mam- 

 malian Ornithorhynchus platypus. Whether these eggs 

 have been abstracted from the collection at some period 

 subsequent to 1838, or whether they have merely been 

 mislaid during one of the many changes which the museum 

 collections have since undergone, is uncertain. 



A paper was read "On the Discharge of Electricity through 

 Gases — illustrated by experiments," by Arthur Schuster, 

 Ph.D., F.K.S. 



Ordinary Meeting, November 18th, 1884. 



Professor W. C. Williamson, LL.D., F.RS., President, 

 in the Chair. 



" On the Reversion of the Minima of the Double-period 

 Variable Star R SagittoR^' by Joseph Baxendell, F.RS., 

 r.RA.S. 



On the 2nd of March, 1880, I communicated to the Phy- 

 sical and Mathematical Section a paper on this star, in which, 

 after giving the results of my observations up to that time, 

 I remarked that " the mean difference between the magni- 

 tudes at the two minima is slowly decreasing, and it will 

 therefore be interesting to watch whether this decrease will 

 go on until the difference entirely disappears and the star 

 becomes a single period variable ; or whether the difference 



