32 PROCEEDINGS OF THE 



1. Sponges. — I have not as yet obtained any definite information 

 of the ravages of this class, although I fully anticipate that indica- 

 tions of their presence will ultimately be met with. That bur- 

 rowing sponges (? of the Cliona type) existed in the Carboniferous 

 seas is, I think, abundantly proved by the condition of the shells 

 of our common Ghouetes, which at many localities — e.g., East Barns, 

 near Dunbar, and Jloscobie quarry, are met with, riddled with 

 passages and galleries of peculiar form, resembling those of sponges 

 in shells of the present day. These I have briefly noticed else- 

 where,* and I would recommend this branch of the enquiry to 

 those possessed of material likely to yield good results. 



2. Annelida. — An interesting specimen, found by Mr. James 

 Bennie, leads me to think that in all probability Annelides took 

 some part in these enlargements. Examine PL I. fig. 1 8 attentively : 

 at the extreme edge of the large fractured surface will be seen two 

 small holes in the Crinoid stem — the larger of which, when highly 

 magnified, will be seen to be filled by a small black tube of shining 

 material. On viewing the fractured surface this becomes much 

 more apparent, pursuing its way towards the columnar canal, and 

 near the centre becoming lost in an undistinguishable mass. To 

 those accustomed to work amongst Carboniferous fossils, the 

 aspect of the shining, horny-like tubes of Serpidites will be familiar, 

 especially when possessing the delicate bloom which indicates con- 

 version into Vivianite — a peculiar phosphate of iron. The little 

 body penetrating this stem has such an appearance, and although, 

 so far as I am aware, no evidence has yet been brought forward to 

 show that the Carboniferous forms of Serpulites possessed burrowing 

 powers, still, the resemblance is so strong that I cannot but refer 

 the object in question to Serpulites, for want of a better resting- 

 place. Unfortunately, this is the only specimen we possess, other- 

 wise microscopic sections prepared from it would doubtless have 

 thrown further light upon the matter. 



V. — Recapitulation and Conclusion. 



The extent of our published knowledge on this subject appears 

 to be this — 



First. — Enlargement may be caused by the loss of a side-arm 

 and subsequent repair of the parts. In the only well-defined 



*Geol. Mag., Dec. 2, 1847, IV., p. 319. 



