VI 



Page 



Ridley, Stuart 0., F.L.S., Assistant in the Zoological Department, 

 British Museum. 



On two Cases of Incorporation by Sponges of Spicules foreign to 

 them 149 



Ridley, Stuart 0., M.A., F.L.S., and Prof. P. Martin Duncan, 

 M.B.Lond., F.R.S., F.L.S. 



On the Genus Plocamia, Schmidt, and on some other Sponges 

 of the Order Echinonemata ; with Descriptions of two 

 additional new Species of Dirrhopalum. (Plates XXVIIT. & 

 XXIX.) 476 



Sorby, Henry C, LL.D., F.R.S., F.L.S., Vice-Pres. Geol. Soc. 



On the Green Colour of the Hair of Sloths. (With a woodcut.) 337 



Stewart, Charles, F.L.S., Lecturer on Comp. Anat. ; St. Thomas's 

 Hospital. 



Note on an Abnormal Amblypneustes grisens. (Plate V. in part.) 130 



Watson, Rev. Robert Boog, B.A., F.R.S.E., F.L.S., F.O.S., &c. 

 Mollusca of the l Challenger ' Expedition : — 



Part V. Families Solenoconchia, TROCHiDiE, Hetero- 

 PHROSYNiDiE, LiTORiNiDiE, Cerithiid^e, and genera and 



species of. (With a woodcut.) 87 



Part VI. Turritellid^e. (With a woodcut.) 217 



Part VII. Families Pyramidellid^;, Naticid.e, Cassidea, 



Tritonhle, and genera and species of 245 



Part VIII. Pleurotomidje 388 



Part IX. Pleurotomid^e (continued) 413 



Part X. PLEUROTOMiDiE (continued). (With 2 woodcuts.). 457 



