THE VOYAGE OF H.M.S. CHALLENGER. 
recent Asteroidea, with their geographical and bathymetrical distribution, 
and a full account of all synonyms and changes of name are given; every 
known starfish is believed to be included, and the recognition of “ good 
species ” and “synonyms” is based on personal observation (except in the 
case of some American types and a few recently described from the French 
dredgings). 
The Report may be considered a monograph on the group, though of 
course it need hardly be said that previously described and recognised 
species are not re-described. An entirely new classification of the Aster- 
oidea has been given—it was very unsatisfactory and quite unworkable 
previously. 
All naturalists who appreciate careful and accurate work will join with 
me in congratulating Mr. Sladen on the completion of his valuable memoir, 
which extends to 935 pages, and is illustrated by 118 lithographic plates 
and a map. 
JoHN MurRAY. 
CHALLENGER OFFIcE, 32 QuEEN SrREET, 
EpinpurGH, January 23, 1889. 
