155 
SECOND REPORT on the PORIFERA of the L.M.B.C. 
: DISTRICT. 
By RicHarpD Hanirscu, Ph.D., 
DEMONSTRATOR OF ZOOLOGY IN UNIVERSITY COLLEGE, LIVERPOOL. 
With Plates V., VI. and VII. 
[Read 8th February, 1889.] 
StncE the publication in 1886 of the “‘ First Report upon 
the Porifera,’ by Mr. Thomas Higgin, F.L.8., in the first 
volume of ‘The Fauna of Liverpool Bay,” several very 
important works upon the Sponges have appeared which 
have changed to a considerable extent the accepted 
views as to the classification of the group, and render 
a re-arrangement of the species dealt with in the former 
report absolutely necessary. I have found it convenient 
to arrange the Sponges in the followimg groups :— 
Myxospongie, Ceratosa, Monaxonida, Tetractinellide, 
Hexactinellide, and Calcarea. I regard these groups as 
orders, although I do not wish to state that they are all 
equivalent to each other. Every one of these orders, 
except the Myxospongiz, has been treated of in a separate 
“Challenger”? Report, and this fact justifies my classi- 
fication sufficiently. In the further division of the 
orders I shall accept Ridley and Dendy’s system for the 
Monaxonida, and Sollas’s system for the Tetractinellide. 
In regard to the Calcarea, I shall follow Mr. Higgin’s 
example and use Haeckel’s classification, instead of that 
of Polejaeff. The Sponges in our district belonging to the 
remaining orders are so few in number that any further 
classification of them is unnecessary. 
I will add an explanation, why I did not follow the 
latest classification of the sponges given by R. v. Lendenfeld, 
