Vlll 



Page 



21. On the Spei'iiiatophores in Earthworms of the Genus 



Pheretima ( = Perichceta). By Frank E. Beddard, M. A. , 

 F.R.S., F.Z.S., Prosector to the Society. (Text-figs. 

 ] 34-136.)... ,.. 412 



22. A Rare Beaked Whale. By R. Lydekkek. (Text-figs. 



137-139.) 420 



23. Age- Phases of the RorquaL By R. Lydekker 423 



24. On Longevity and Relative Viability in Mammals and 



Birds .; with a Note on the Theorj'" of Longevity. By 

 P. Chalmers Mitchell, M.A., D.Sc, LL.D., F.R.S., 

 Secretary to the Society 425 



25. Some new Parasitic Nematodes from Tropical Afi'ica, 



By Robert T. Leiper, D.Sc, M.B., F.Z.S. (Text-figs. 

 140-144.) 549 



ADDENDUM. 



A correction to Dr, R. T, Leiper's Memoir on the " Entozoa 



of the Hippopotamus " - . 555 



