Grayella, Osculina, and Cliona. 81 



wlicre, imdor Dr. Gray's name of " Pione,^^ lie states that 

 Cliona northumhrica is not uncommonly dredged off tlie south 

 coast of Devon, " in Biiccimim nnd(ttu7/i and in tlic old valves 

 of Cardium eduhj^ testifying at the same time to the " excel- 

 lent" description of this species, in the 'Annals,' by Mr. 

 Albany Hancock. 



In my specimen, which is not much the worse for ten days' 

 contincment, there are no raised areohe of sponge-substance 

 (spicules and sareode) bordering the holes in the oyster- 

 shell, as in the specimens of Cliona celata and Raj)hyrus 

 Griffiihsii to which I have alluded ; and I think it not impro- 

 bable that, although the ])apilla3 would be much contracted by 

 death, still some of them would remain much Ix-yond the 

 holes in the oyster-shell, which, if dissolved off, Avould give 

 them a similarly elevated position above the other sj)onge- 

 substance to that presented by the papilla3 in Grayella and 

 Oscalina. 



Postscript. 



Since the above was written, three or four of the inhalant 

 papilU\3, now in a semieontracted condition, on the concave 

 side of the oyster-shell, have presented a single funntd- 

 shaped hole in the centre respectively, which, being so nmch 

 larger than the original apertures, led me to think that they 

 must be vents ; but on placing them under the microscope, 

 particles were observed to be Avhirled into them, apparently in 

 a sj)iral manner, showing at once that they were not vents, 

 and affording positive evidence, which had not been before 

 obtained, of the inhalant function of these papilla?. 



The vents are still active, and the inhalant papilla? as sen- 

 sitive to light as when first the Cliona was placed in con- 

 finement (now thirteen days ago), which would hardly have 

 been the case had the Cliona not been drawing its nourish- 

 ment from the organic matter in the oyster-shell. On the 

 other hand, a living piece of Raphyrus GriJfitJisii (which I 

 regard as a free form of Cliona celata)^ and which was })laced 

 in sea-water renewed as often as that of the Cliona, ceased, 

 after three days, to show any active signs of life what- 

 ever. 



The papillit which presented respectively the single funnel- 

 shaped hole in the centre were, with the exception of the rim, 

 very like Schmidt's figs. 10 e<: 11 of Osculina pohjstomella 



Finally, it should be noticed that the papilla? in Cliona 

 nortlnunbrica ceased to present their fimbriated forms about 

 the sixth day after confinement, and, showing signs of decline 



