102 



The Chairman said anything from Mr. Morland on the subject of diatoms 

 was sure to be of interest, and though he did not himself give much atten- 

 tion to objects of this kind he might say that it seemed a very extraordinary 

 thing that two such utterly opposite things should belong to the same 

 species. It showed how careful persons should be not to hastily make new 

 species from the observation of differences in the markings alone, though it 

 was not very often that anyone had the good fortune to find the two valves 

 together as Mr. Morland had done. 



Mr. Smith said it was quite possible for a valve to be found which had a 

 different pattern on different sides, in illustration of which he drew a 

 diagram upon the board of a specimen of Airfacodiscus as he had seen it 

 under a 1 V m * immersion objective. 



Mr. Morland said this was not a question of difference of structure on 

 different sides, but rather that of two distinct valves of the same species. 

 There was a distinct space seen between the two, with a bubble of air 

 between them. He could give another instance in the case of Cocconeis, 

 recent specimens of which could be found in situ. 



Mr. Karop said that the specimens exhibited the other night had all the 

 appearance of being genuine valves belonging to one and the same frustule. 



The thanks of the meeting were voted to Mr. Morland for his communi- 

 cation. 



Announcements for the ensuing month were then made, and the proceed- 

 ings terminated with the usual conversazione, and the following objects 

 were exhibited : — 



Head of " Devil's Coach Horse," Ocvpus") 



i •«, , i *. a I Mr. F. Knock. 



olens, with explanatory drawing ... ) 



Diatoms, Coscinodiscus centralis, from Sheer-") 



... ... ... s Ut - t - w - Smith - 



„ Coscinodiscus centralis, from Not-) 

 tingham (Maryland) deposit ) 



Attendance — Members, 27; Visitors, 0. 



August 12th, 1887. — Conversational Meeting. 



The following objects were exhibited by Mr G. E. Mainland: — 

 Pupa of the Hessian fly, Cecidomyia destructor, and the stigma and 

 pollen of Phlox, sp. 



Attendance — Members, 15 ; Visitors, 0. 



August 26th, 1887. — Ordinary Meeting. 



.J. G. Waller, Esq., F.H.A., in the Chair. 



The minutes of the preceding meeting were read and confirmed. 

 The following additions to the Library were announced : — 



" Proceedings of the Koyal Society " ... ... In exchange. 



" The American Monthly Microscopical Journal " ,, 



