On new Recent Pharetronid Sponges. 503 



these species occur in the Mediterranean), bat the probability 

 is too slight to permit the use of his name. As far as Brady's 

 description of 0. challengeri goes it is applicable to both 

 setigera and 0. pelagica ; but the absence of any reference 

 to or figure o£ the outer-edge setae of the basipodites of the 

 swimming-feet prevents a definite conclusion being reached. 



With regard to recent records of 0. plumifera and 0. seti- 

 gera, we find in the ' Quarterly Bulletins of the International 

 Council for the Investigation of the Sea' that 0. plumifera 

 occurs in the plankton lists of Denmark, Norway, Sweden, 

 Holland, Germany, Russia, England, and Ireland. The 

 Irish records, for which I am responsible, refer to the species 

 described above as 0. atlantica t as do likewise the records in 

 the various papers in the ' Reports on the Sea and Inland 

 Fisheries of Ireland.' The quarterly plankton lists of 

 Scotland contain both 0. setigera and, more rarely, 0. plumi- 

 fera, and Dr. T. Scott * has recorded 0, setigera from the Firth 

 of Forth and from off Shetland. It seems probable that 

 some, at any rate, of these records refer to one or other of the 

 species described above ; and even if the points which I have 

 relied on in separating the species should be regarded as of 

 varietal rather than of. specific rank, it is still incumbent on 

 those who record the species for statistical purposes to indicate 

 which variety is referred to. 



LXIX.- — On Two new Genera of Recent Pharetronid Sponges. 

 By R, KlRKPATKICK. 



[Plates XIII.-XV.] 



When looking through some material in a large bottle mostly 

 containing pieces of Stylaster sanguineus, obtained by the 

 ' Challenger ' from a depth of 70 fathoms off Api, New 

 Hebrides, I came across two specimens which at first sight 

 looked like pieces of Millepora. A closer inspection, how- 

 ever, showed them to be Lithonine sponges, and of great 

 interest, because the soft tissues have been fairly well pre- 

 served. The sponges belong to a new genus and species, 

 which I propose to name Mmchinetta f lamellosa. A second 

 new genus must be established to include certain sponges 



* 'Ninth Ann. Rep. F. B. Scotland' (1891) ; 'Twentieth Ann. Rep, 

 F. B. Scotland ' (1902). 



t Named in honour of Prof. E. A. Minchin, M.A-, Professor of Proto^ 



/.,'jojogy in the University of London, 



36* 



