Vll 



Page 



46. On an Instance of Oommensalism between a Hermit 



Crab and a Polyzoon. By R. Kirkpatrick, F.Z.S., 



and Dr. J. Metzelaar. (Plates I. & II.) ' 983 



47. New Species of Trinidad Moths. By W. J. Kaye, 



F.E.S. (Plate I.) 991 



48. Tlie Nematode Grenus Physaloptera Rud. By R. J. 



Ortlepp, M.A., Research Assistant, Dept. of 

 Hehninthology, London School of Tropical Medicine ; 

 Hon. Parasitologist to theSociety 1921-1922. (Text- 

 figures 1-44.) 999 



49. The Oligochfeta of the Oxford University Spitsbergen 



Expedition. By J. Stephenson, M.B., D.Sc, F.Z.S., 

 Lecturer in Zoology, Edinburgh University. (Text- 

 figures 1-6.) 1109 



50. On the Anatomy of Scaphula Benson, with a description 



of a new Species. By Ekenbranath Ghosh, M.Sc, 

 M.D,, F.Z.S., F.R.M.S., Professor of Biology, Medical 

 College, Calcutta. (Text-figures 1-7.) 1139 



51 . The Foetal Membranes and Placentation of Ghiromys 



madagascariensis. By Prof. J. P. Hill, F.R.S., and 

 R. H. Burne, M.A. (With an Appendix on the 

 External Characters of the Foetus, by R. I. PococK, 

 F.R.S.) (Plates I.-VI. ; Text-figures 1-6.) 1145 



52. On the External Characters of the Beaver (Castoridce) 



and of some Squirrels {Sciuridce). ]ij R. I. PococK, 

 F.R.S. , F.Z.S. (Text-figures 38-60.) 1171 



53. On the Morphology of the Chondrocranium of the 



Larval Herring {Clwpea harengus). By F. R. Wells. 

 (Text-figures 1-11.) 1213 



54. On the Colours of Water-Mites. By C. S. Elton, New 



College, Oxford 1231 



55. Notes on certain Crossopterygians. By Erik A : son 



Stensio, Upsala. (Plate I. ; Text-figures 1-6.) 1241 



