NOEMANIA. 29 



NOBMANIA OEASSA, BoW., Ill, 258; PI. LXXXI, figs. 1— 

 12. 



1868 Normama orassa, Bowerbank. Last Report of Dredging 

 among the Shetland Isles ; Norman on the Porifera 

 (Brit. Assoc. Rep.), 1868, p. 328. 



The type-specimens were dredged in 110 fathoms 

 20—25 miles N.N.E. of Burrafirth Lighthouse, Shet- 

 land; but the small specimens mentioned (III, 262) 

 are erroneously recorded by the author as from 

 Shetland. They were dredged by me in company with 

 Dr. G-wyn Jeffreys in the Minch in 1866. 



Mr. Carter (' Ann. Nat. Hist.,' ser. 5, vol. ii, 1878, 

 p. 176) has stated that " the type-specimen of Dr. 

 Bowerbank's Normania crassa is only a sessile form of 

 Tethya muricata, in every respect similar to one which 

 was dredged up on board H.M.S. ' Porcupine.' Tethya 

 muricata is better known as Wyvillethomsonia Wallichii, 

 a sponge which will, after bearing many synonyms, 

 probably have to settle down as Thenea m/u/ricata 

 (Bow). Mr. Carter speaks very confidently respecting 

 the type of Normania crassa, a sponge which is in my 

 cabinet, and which he has never seen, but he has fallen 

 into an extraordinary error. I know not well how two 

 sponges belonging to the same group could well be 

 more distinct than the two, which he would thus syno- 

 nymise. They not only differ altogether in all external 

 characters, but their spicula are wholly different. 

 Without going into further detail it will suffice to 

 state that the most characteristic " attenuato-expando- 

 ternate " bifurcating connecting and defensive spicules 

 of Thenea, figured by Bowerbank (' Proc. Zool. Soc.,' 

 1872, pi. V, fig. 4) and by Kent ('Month. Micros. Jour.,' 

 vol. iv, 1870, pi. Ixvi, figs. 6, 7) the " simple attenuate- 



