92 SAGARTIAD.E. 



this in Protean variability. And yet there is, in general, 

 no difficulty in determining the species ; the characteristic 

 B is an excellent note of distinction wherever it is present ; 

 and in those varieties in which it is obliterated in the 

 evanescence of the markings, as in vars. fi, v, £, o, or 

 merged in the abnormal spread of the dark hue of the disk, 

 as in vars. ir, p, a, v, the true character of the specimen 

 will be betrayed by the form and substance of the body, 

 the drab colouring of the column, or the tendency of the 

 tentacles to assume the orange hue.* 



It is one of our most generally distributed species, rang- 

 ing apparently all round our coasts, from east to west, and 

 from north to south. It is also tolerably abundant, at least 

 in many of its localities, though less liable than some to 

 be seen by casual observers, from its habits of retirement. 

 Mr. Price well characterised it, when he proposed for it the 

 name of troglodytes (" cave-dweller," from rpcoyXr), a cavern, 

 and Svvco, to enter) ; for its favourite habit is to ensconce 

 itself in holes and crevices of the solid rock, into which it 

 retreats on alarm. In the shallow pools that floor the largest 

 of the caves at St. Catherine's, Tenby, the vars. scolopacina 

 and aurora are abundant, especially the former, spreading 

 their pretty blossom-faces at the bottom of the clear water. 

 And yet it is not easy to discover them even when scores 

 are thus exposed ; for the mottled colouring of the disk and 

 tentacles is so like that of the sand and mud of the pools, 

 that even a practised eye may overlook them without the 

 closest searching. They often protrude the tentacles only, 

 clustered perpendicularly, through the mud, and sometimes 

 only the tips of these organs. Their concealment is aided 

 by the fragments of sand, gravel, and broken shells, that 



* " In addition to these characteristics, I think the stout firm texture of 

 the base a fair mark, as it is not so readily injured as in most species. 

 Also the comparatively slight adhesion, at least when you can get fairly 

 down to it : I think it generally yields to careful fingering." (F. H. W. 

 in litt.) 



