Scrobicularias, Mud Residents and Fish Food. 219 



(c) The SCROBICULARIA (various sorts) within our District 

 constantly contribute provender for plaice and dab, and in 

 season are preyed on by the flounder, while in the North Sea 

 haddocks and cod are particularly fond of them. Outwardly 

 to a certain extent they resemble the Tellinas ; like them, bed 

 gregariously, and are residents of mud, sand and clayey soil. 



The PEPPERY SCROBULARIA (&. piperita), relatively a large 

 form (1J by 2 inches diameters), is of common occurrence at 

 Walton-on-Naze, Harwich, Felixstowe, &c. (Crouch), though 

 not found by him in his dredging in the Burnham river.* It 

 has been got at several places on the Kentish shores, Pegwell 

 Bay, Reculvers, &c. In digging for clams (Mya) on the fore- 

 shore clyty-mud close to Leigh, we have come across great 

 batches in family groups. These occupy the top layers, 2 to 3 

 inches from the surface, whilst clams lie below them, but much 

 more deeply situated. The syphon tubes of Scrobicularia, like 

 those of Tellina, are separate, and at times stretch out and are 

 thrust upwards to the water (see sketch, fig. 24). Other much 

 smaller, more delicate species, 8. alba, S . prismatica, and S. tennis 

 with varieties, are numerous on our shores, the last one supposed 

 to become the food of the grey mullet. " Butterfish " is a local 

 name given to specimens of Scrobicularia and Tellina indis- 

 criminately. 



(d) The MACTRAS, of stouter build and shaped something 

 like Scrobicularia (but with united syphons as in the clams and 

 other likenesses), only furnish food for fish in our area, though 

 elsewhere they are used as bait, and occasionally partaken of as 

 edible product. M. solida, M. subtruncata and M. stultorum are 

 freely distributed on various parts of our littoral and estuaries. 

 The last named turned up in enormous quantities when dredg- 

 ing the harbour of Newhaven (Sussex) in 1861. Barges trans- 

 ported the dredgings outside, whither flocked flat fish in such 

 multitudes that the trawlers reaped a golden harvest close 

 in shore (Jeffr., Brit. Conch., Vol. II.). 



*Essex Nat. VI. (1892). Yet this does not imply its absence in the marginal muddy 



sands there. 



