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RAY SOCIETY VOLUME FOR 1918. 



THE BEITISH FEESHWATEE EHIZOPODA AND HELIOZOA. 

 By J. Cash and G. H. Wailes, F.L.S., assisted by J. Hopkinson, 

 F.L.S., etc. Volume IV. Supplement to the Ehizopoda by G. H. Wailes, 

 and Bibliography by J. Hopkinson. 8vo. pp. xii + 130, with 6 plates. 

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