170 BRITISH SPONGES: 



Mr M'Colla is of opinion that S. limbata is an annual spe- 

 cies, since he found it in November, and there was no appear- 

 ance of it during the summer months. Its term of existence 

 can, at all events, not exceed that of the Fucus it grows upon, 

 and this is usually an annual. 



3. S. ? L^viGATA, " soft, compressible, and elastic ; tex- 

 ture extremely Jine and reticidated." 



Spongia laevigata, Montagu in Wem. Mem. ii. 95, pi. 16, fig. 4. 



Flem. Br. Anini. 526. 

 Scypha lcE\'igata, Gray, Br. PI. i. 358. 



Hah. Coast of Devon ? very rare, Montagu. 



." This is the most delicate of all the soft British sponges ; 

 when compared with either oculata or dichotoma, their texture 

 is extremely coarse ; by the naked eye, the surface appears nearly 

 smooth, or finely frosted ; when examined with the double lens 

 of a megalascope, the surface is found to be minutely and ele- 

 gantly reticulated, and of a cottony softness, but the fibres are 

 infinitely finer than common cotton. Perhaps the texture in fine- 

 ness would be more aptly compared to the interior spongy part 

 of some species of puflf-ball, (Lycoperdon.) 



" The only small piece of this sponge that has come under 

 observation is tubular throughout ; whether this is its natural 

 habit, or the consequence of being a parasitical species that sur- 

 rounds the stalks of fuci, or other marine plants, has not been 

 discovered ; but it is observable, that the central fibres radiate 

 to the circumference ; the summit, however, is rounded and per- 

 fect, like the finish of an independent species." Montagu. 



A Spongia prolifera is enumerated among the sponges 

 of the Firth of Forth by Dr Grant, (Edin. Phil. Journ. xiv. 

 116,) but he has given no description of it. The sponge refer- 

 red, (erroneously as I believe,) by Templeton to the *S'. prolifera 

 of Ellis and Solander, and dredged apparently in Belfast Lough, 



