CONTENTS. 



PAGE 



On Pelomyxa viridis, sp. n., and on the Vesicular Nature of 

 Protoplasm. By Alfred Gibbs Bourne, D.Sc.(Lond.), C.M.Z.S., 

 F.L.S., Fellow of University College, London ; Fellow of Madras 

 University ; Professor of Biology in the Presidency College, 

 Madras. (With Plate XXVIII) . . . .357 



The Medusae of Millepora niurrayi and the Gonophores of 

 AUopora and Distichopora. By Sydney J. Hickson, M.A., 

 D.Sc, &c., Fellow of Downing College, Cambridge. (With 

 Plates XXIX & XXX) 375 



On a Red Pigment -forming Organism, B. corallinus. By 

 Charles Slater, M.B.(Cantab.) (With Plate XXXI) . 409 



CONTENTS OF No. CXXVIII, N.S., OCTOBER, 1891. 



MEMOIRS : 



Immunity against Microbes. By M. Armand Rtjffer, M.A., 

 M.D.(Oxon.). (With Plates XXXII & XXXIII) . . 417 



The Formation and Fate of the Primitive Streak, with Observations 

 on the Archenteron and Germinal Layers of Rana temporaria. 

 By Arthur Robinson, M.D., Senior Demonstrator of Anatomy 

 in the Owens College; and Richard Assheton, M.A., Demon- 

 strator of Zoology in the Owens College. (With Plates XXXIV 

 & XXXV) 451 



On some Points in the Histology and Development of Myrio- 

 thela phrygia. By W. B. Hardy, B.A., Shuttleworth Scholar 

 of Gonville and Caius College, and Junior Demonstrator of 

 Physiology to the University of Cambridge. (With Plates 

 XXXVI & XXXVII) 505 



On the Structure of an Earthworm allied to Nemertodrilus, 

 Mich., with Observations on the Post-embryonic Development of 

 Certain Organs. By Frank E. Beddard, M.A., Prosector of 

 the Zoological Society of London, Lecturer on Biology at Guy's 

 Hospital. (With Plates XXXVIII & XXXIX) . . 539 



Some Points in the Development of Scorpio fulvipes. By 

 Malcolm Laurie, B.Sc, F.L.S. (With Plate XL) . . 587 



