246 Bibliographical Notices. 



dcTititioii of the vole *, 25 per cent, of specimens examined 

 may be abnormal, a fact which, when still larger numbers 

 are available, may yet prove the saving of my subdivision 

 of tlie he.lgehogs. 



In conclusion, I must thank my critic for the exceedingly 

 temperate and forbearing way in which his remarks are 

 couched. Criticisms thus conscientiously formed and fairly 

 expressed Ciinnot surely fail to advance our science. 



BIBLIOGliAPHlCAL NOT[CP:S. 



Zooloyical Results ba^ed on M.iterial from N^ew Britain, Neiv Guinea, 

 Lounlti/ Islands, and elsewhere, collected diiring the Years 1895, 

 1896, '(OifM 897, hi i Arthur WiUetj, D.Sc. Loud., Hon. M.A. 

 Cantah. Part IV. ^Cambridge, May 1900. 



The long-delayed fourth part of Dr. Willey's ' Zoological Results ' 

 is now before us and proves fully equal, both in interest and iu the 

 general excellence of its contents, to its predecessors. It contains ten 

 mennnrs, the majority of which are devoted to reports on the collec- 

 tions made by Dr. Willoy in various groups of the animal kingdom. 

 Three, however, are on subjects of morphological intere»t. The first 

 of these is the opening paper of the volume by Mr. J. Stanley 

 Gardiner, " On the Anatomy of a supposed new Species of Cceno- 

 psanuniii from Lifu.'' Mr. Gardiner divides his subject into four 

 heads, dealing respectiveh' with the general anatomy of the skeleton 

 and specific description, the general anatomy of the polyps, minute 

 anatomy, and some conclusions relating to the body-layers in the 

 Actinozoa. He comes to the conclusion that the whole filament of 

 the primary and secondary, and probably also that of the tertiary, 

 mesenteries is ectodermic in origin, and that the whole of the 

 digestion of the animal is performed by these filaments, and draws 

 the important deduction that the stomodajum of Actinozoa is not 

 comparable with that of the Triploblastica, but is rather, with 

 the mesenterial filaments, the homologue of the whole gut. The 

 so-called endoderm is homologous with the mesoderm of Triplo- 

 blastica, and the Actinozoan polyp ought to be regarded as a Triplo- 

 blastic form. 



The second of the morphological papers is by Mr. J. J. Lister on 

 Astrosclera Willeyawi, the ty])e of a new family of sponges. This is 

 a very remarkable organism, with a massive calcareous skeleton of 

 polyhedral elements united to form a rigid skeleton and excluding 

 the soft parts, an arrangement which is only approached among 

 living sponges in the genus Pttrostoma. Among several points in 

 which Astrosclera differs from the rest of the Porifera may be men- 

 tioned the absence of a central atrial space, the minute size of the 

 flagellated chambers, and the peculiar form of the fiagellated cells, 

 * As phown bv Mr. G. S. Miller, Jun. 



