192 



THIKD KEPOET on the POKIFEEA of the 

 L.M.B.C. DISTEICT. 



By Kichard Hanitsch, Ph.D., 



DEMONSTRATOR OF ZOOLOGY IN UNIVERSITY COLLEGE, LIVERPOOL. 



With Plates X.— XV. 



[Read 9tli May, 1890.] 



In the two previous reports* on the Porifera of the district 

 forty-four species were recorded, one of which was new to 

 British seas and three new to science. Several cruises in 

 Liverpool Bay during the summer of 1889 and the present 

 spring, and also shore- working at the Biological Station, 

 Puffin Island, in April, 1889, and at Port Erin, Isle of 

 Man, last April, enable me to add twelve species to 

 the record, three of which are new to science, making in 

 all fifty- six species. 



In my former report I fell into a serious error in regard 

 to the structure and systematic position of Seiriola compacfa, 

 n. sp., and I desire to acknowledge my indebtedness to 

 Professor Sollas, D. Sc, for the great kindness with which 

 he has pointed out the mistake to me and has answ^ered 

 many questions having a bearing on that species. I give 

 now a re-description of Seiriola compacta (see below). 



The following table gives all sponges found up to the 

 present date in the district, and show^s the distribution of 

 the species in the four parts in which they have been most 



* "Report on the Porifera of the L.M.B.C. District." by Thomas Higgiii, 

 F.L.S., in " Fauna of Liverpool Bay," Vol, L, 1886. And " Second Report on 

 the Porifera of the L.M.B.C. District," by R. Hanitsch, in Proc. Biol. Soc, 

 Liverpool," Vol. IIL, 1889, and "Fauna," Vol. IL 



