8 PROCEEDINGS OF THE 



Dr. Albert John Chalmers and Mr. Thomas James Evans, 

 M.A., were elected reJlows. 



Prof. F. O. Bower, Sc.D., P.R.S., F.L.S., gave a lecture on 

 " The Morphology of the 8orus of Ferns," the following theses 

 being iiiaintaiued and illustrated in a long series of lantern-slides 

 of living and fossil species : — 



1. The isolated sporangium (monangial sorus of Prantl) is 



frequent among primitive Filicales. 



2. The distal or marginal position of the soi'us is prevalent 



in primitive types. 



3. The transition from a marginal to a superficial position 



has frequently occurred. 



4. Interpolation of sporangia has led to increased complexity 



of the sorus. 



5. In simple, gradate, and mixed sori thus constituted the 



receptacle varies : it is not a stable entity, but a result 

 of elaboration of the vein-ending on whicli the sporangia 

 are seated. 



6. Superficial extension of sori occurs. 



7. Duplication of sori also occurs. 



8. Fusion of sori occurs progressively in various phyla. 



9. The fusion-sorus may disintegrate, but not necessarily 



along the original lines of fusion. 



10. The identity of the sorus may be lost by acrostichoid 



development, which has occurred along numerous lines 

 of phyletic advance. 



11. The more complex sori of Ferns, as they are now seen, 



are referable along such lines of comparison to marginal 

 or distal monangial sori. 



12. Such a position of isolated or few sporangia is found to 



prevail in plants of the Lower Devonian Period. 



13. The marginal placentatiou of Seed-Plants is probably 



more than a mere analogy. 



Dr. D. H. Scott, F.E.S., Prof. J. B. Farmer, F.E.S., and 

 Mr. W. C. Worsdell discussed some of the points raised, and 

 Prof. Bower replied. 



February 1st, 1917. 

 Sir David Prain, C.M.G., F.E.S., President, in the Chair. 



The Minutes of the General Meeting of the 18th January, 

 1917, were read and confirmed. 



Mr. Frederick Moore Clements, F.Z.S., Mr. Henry James 

 Davies, F.K.S.A., the Eev, James Marchant, and Mr. Henry 

 Pelix Nortbcote, were proposed as Fellows. 



