VI CONTENTS. 



IX. Aster oidea dredged in the Faeroe Channel during the Cruise of 

 H.M.S. "Trito?i" in August 1882. By W. Percy Sladen, 

 F.L.S., F.G.S. Communicated by John Murray, F.R.S.E. 

 (Plate XXVI), . 153 



X. On a New Species of Pentastomum (P. protelis) from the Mesentery 

 of Proteles cristatus ; with an Account of its Anatomy. By 

 W. E. Hoyle, M.A. (Oxon.), M.R.C.S., Naturalist to the 

 "Challenger" Commission. (Plates XXVIL, XXVIIL), 165 



XL On Superposed Magnetisms in Iron and Nickel. By Professor 



C. G. Knott, D.Sc. (Plate XXIX.), . ' . . .193 



XII. On the Relative Electro- Chemical Positions of Wrought Iron, Steels, 

 Cast Metal, <%c, in Sea Water and other Solutions. By Thomas 

 Andrews, A.M., Inst. C.E., F.C.S. (Plates XXX.-XXXIV.), 204 



PART II. (1883-84.) 



XIII. Report on the Tnnicata dredged during the Cruises of H.M.SS. 

 " Porcupine " and " Lightning " in the Summers of the Years 

 1868, 1869, and 1870. By Professor Herdman, F.R.S.E. 

 (Plates XXXV., XXXVL), 219 



XIV. Note on Sir David Brewster's Line Y in the Infra-Red of the Solar 

 Spectrum. By Professor Piazzi Smyth, F.R.S.E., Astronomer- 

 Royal for Scotland. (Plate XXXVIL), , t . . 233 



XV. On the Formation of Small Clear Spaces in Dusty Air. By John 



Aitken, F.R.S.E. (Plate XXXVIII.), . .239 



XVI. On Stichocotyle Nephropis, a New Trematode. By J. T. Cun- 



ningham, B.A. (Plate XXXIX.), . . . .273 



XVII. The Enumeration, Description, and Construction of Knots of 



fewer than Ten Crossings. By Rev. T. P. Kirkman, F.R.S. 

 (Plates XL.-XLIIL), 281 



