176 Mr. H. J. Carter on Tethea miiricata. 



1876, vol. xviii. p. 472). So also Tethea rnuricata may be 

 influenced in this respect under similar circumstances, as will 

 presently appear. 



The long tails (in plurality) of bifid, recurved anchoring- 

 spicules, the long-shafted trifid and once bifurcate " zone- 

 spicules " of the body, the long and smooth acerates, the 

 smaller acerates more or less microspined and more or less 

 inflated in the middle, together with the elongated, subspiral, 

 stellate flesh-spicule, characterize Tethea muricata^ but nothing 

 more than the lace-like, clathrate sarcode densely charged with 

 this peculiar flesli-spicule, which especially hangs about the 

 body just under the margin of the agariciform liead, where the 

 sponge has this form, and in the body generally of the other 

 specimens. It was therefore (as will be seen by a reference 

 to Dr. Bowerbank's illustrations, /. c.) this part in particular 

 which he selected for that purpose, which, being peculiar to 

 Tethea muricata^ at once serves to identify the latter with 

 WyviUethomsonia Wallichn, even if he had not done so him- 

 self through Doy'villia agariciformis [I.e.). 



Further, it may be observed that, the type specimen of 

 Dr. Bowerbank's Normania crassa (Mou. Brit. Spong. vol. iii. 

 1874, p. 257 &c., pi. Ixxxi.) is only a sessile form of Tethea 

 muricatay in every respect similar to one which Avas dredged 

 up on board II. M.S. 'Porcupine.' Both, like the fragment 

 of Euplectella aspergUIum to which I have above alluded, 

 were without anchoring-spicules ; and each possessed a pa- 

 rasitic Palytlioa on its surface, like that on the glass cord of 

 Hyalonema (see pi. Ixxxi. upper margin right side, /. c.) ; so it 

 is not improbable that both, coming from the neighbourhood 

 of the Shetland Islands, may have grown upon hard objects 

 respectively, and not on the subtle mud of the deep-sea bottom. 

 Lastly, the type specimen of Dr. Bowerbank's Hymeniacidon 

 jplacentula [op. cit. pp. 189 and 353, pi. Ixxii.), a species ob- 

 tained respectively from the Hebrides and the Shetland Islands, 

 is also a similar variety of Tethea muricata^ which seems 

 from its compressed form to have been dried under pressure. 



Although, however, this must lead to the suppression also 

 of the names '■^Normania crassa'''' and '''' Hymeniacidon pla- 

 centida''^ (which, together with the sessile specimen dredged 

 up on board the ' Porcupine,' came from the Atlantic Ocean, 

 between the north of Scotland and the Faroe Islands), 

 yet it shows, with what has gone before, that Tethea mu- 

 ricata is equally present off the coast of Norway, off the 

 east coast of Greenland, and in the Bay of Naples, to- 

 gether probably with the North-Atlantic sea-bed gene- 

 rally, where Dr. Wallich's specimens were obtained from the 



