[ vi ] 



XXII. On certain Organs of the Cidaridce. By Charles Stewart, Esq., F.L.S., 

 M.R.C.S., Lecturer on Comparative Anatomy, St. Thomas's Hospital. (Plate 

 LXX.) ' P a g e 569 



XXIII. On Hypsiprimnodon, Ramsay, a Genus indicative of a distinct Family (Pleopo- 

 didee), in the Diprotodont Section of the Marsupialia. By Professor Owen, C.B., 

 F.B.S., F.Z.S., &c, Superintendent of the Natural- History Departments in the 

 British Museum. (Plates LXXI. & LXXII. with 3 Woodcuts.) , ... 573 



XXIV. Descriptions of some minute Hymenopterous Insects. By Prof. J. O. Westwood, 

 M.A., F.B.S., &c. (Plate LXXIII.) 583 



Index 595 



EREATA. 



Page 59, bottom line, for loupe read pocket-lens 

 „ 240, line 15 from top, for N. plicata read N. sinuata 

 „ 566, „ 5 from top, for Albisara read Abisara 

 „ 568, „ 18 from bottom, for Tagisdes read Tagiades 



