278 Dr. W. C. Mcintosh on the Boring of certain Annelids. 



as well as elsewhere, such as several of the Sjpionidce^ Eunice^ 

 Lysidice^ TropJioniaj Syllis armillaris^ Psamathe fusca^ Cos- 

 talia punctata J Eulaliaj Thelepus [Venusia)^ and Aphlebina. 

 Of these, Lysidice is often found under the calcareous spread- 

 ing base of Corallina officinalis along with Leucodore^ under 

 the large littoral Ascidians at Herm, and in masses of Celle- 

 pora from the deep water off St. Martin's Point, Guernsey, 

 and, though it would seem to take possession of an old tunnel, 

 yet appears capable of accommodating the hole to its own 

 wants. Lastly, a few Annelids bore rocks, stones, and shells 

 of various kinds, amongst which are LeucodorCj Dodecaceria^ 

 Sahella saxicava^ Heterocirrus saxicola^ Grube* (a species I 

 cannot at present distinguish from Dodecaceria conctiarurn) ^ 

 besides some of the adjoining group, Gephyrea. 



There is no more common Annelid along the rocky parts of 

 the beach at St. Andrew's than Leucodore ciliata (PL XVIII. 

 fig. 1) ; and, indeed, it is a very abundant British form in general. 

 It especially haunts the soft blue shale at the West and Castle 

 Rocks of the ancient city, apparently, like its companion Pho- 

 la^ crispataj because it finds such more easily excavated than 

 the denser sandstone, just as we see it avoiding the hard gra- 

 nite and gneiss of the Channel Islands and the outer Hebrides, 

 and tunnelling its galleries under the spreading base of Coral- 

 lina and the numerous Nullipores, both free and surmounted 

 by the tangles, or as M. de Quatrefagesf found at Guettary, 

 in the case of Sahella saxicava^ which preferred to bore the 

 calcareous rocks rather than the quartz with which they alter- 

 nated. It is likewise abundant in the fissures of the shale and 

 sandstone, forming tunnels amidst the muddy debris so abun- 

 dant in these localities, where Dr. Johnston seems alone to 

 have found it. (Ersted, again, gives " sandy tubes " as its 

 sole habitation. Vast numbers of the common limpet-shells 

 are also invaded by them, their tracks with the loop at the 

 bottom being visible from the inner surface as whitish streaks; 

 and the irritation frequently causes the moUusk to secrete 

 layer upon layer of the nacreous lining. It abounds likewise 

 in many other littoral and deep-water shells, such as Buccinumy 

 FusuSj Ilaliotisj Ostrea, and Anomia, and, indeed, in favour- 

 able sites, almost upon every shell thick enough to bore into. 



Its presence amidst the shale and sandstone is easily recog- 

 nized by numerous small tubes, composed of agglutinated 

 sand and mud (PI. XIX. fig. 1), which project from the surface 

 of the stone in dense groups, so as to form in many cases a 

 kind of sward of tubes — a habit apparently characteristic of the 



* Archiv fur Natur-es. 1855, p. 108, Taf. 4. f. 11. 

 t Ann. des Sc. Nat. ser. 3. Zool. tome viii. 1847. 



