JOUENALi 



OF THE 



ROYAL MICROSCOPICAL SOCIETY. 



AUGUST, 1912. 



TRANSACTIONS OF THE SOCIETY. 



VII. — Notes on the Life-history of some Marine Diatoms 



from Bournemouth. 



By J. D. SiDDALL, Chester. 

 {Bead April 17, 1912.) 

 Plates III. and IV. 



Eakly in December last my friend, Mr. T. Shepheard, F.R.M.S., of 

 Bournemouth, sent to me a small quantity of material he had 

 obtained by surface-netting from the sea there. Microscopic ex- 

 amination showed that it contained a most varied and interest- 

 ing series of living Diatoms and other Microzoa, including living 

 and dead Foraminifera. Among the Diatoms were Bacillaria para- 

 doxa, Coscinodiscus, Biddulphia, Triceratium, Pleurosigma, etc. ; 

 and the Foraminifera included Miliolina, Entosolenia, Textularia, 

 Bolivina, Botalia, etc.* 



Small portions of the material put into shallow troughs, and 

 laid almost flat for a time to allow the living organisms to creep 



♦ Mr. Earland points out that none of the Foraminifera are pelagic, and their 

 presence in the tow-net can only be attributed to wave action, which is known to 

 extend in the Channel and North Sea down to about 40 fathoms. 



EXPLANATION OF PLATE III. 



Coscinodiscus heliozoides. 



Drawn from living examples found in a surface-netting from the sea at 

 Bournemouth, made by ]\Ir. T. Shepheard, December 2, 1911. X 640. 

 Colour should be yellow-brown. 



Fig. 1.— Flat. Fig. 2.— Edgewise. 



Aug. 21st, 1912 2 D 



