HARMOTHOE IMBRICATA. 319 



short tips from the middle of the foot (Plate XXXVIII, fig. 16) the same relations of the 

 secondary process occur, and thus they are easily discriminated from the bristles of 

 Lagisca floccosa. The ventral cirrus has a series of short clavate cilia. 



In the terminal feet the dorsal bristles remain stout, but their tips are more 

 tapered. The slender ventral bristles, on the other hand, have the spinous region 

 greatly elongated, but the delicate tips in most cases retain the bifid condition, only one 

 or two at the ventral border being simple. 



Varieties. — A variety procured by Canon Norman in Norway has shorter bristles, 

 but though the rows of spikes on the dorsal bristles are somewhat finer, in all other 

 respects it corresponds. In another from Loch Portan, Lochmaddy, the dorsal bristles 

 immediately above the ventral are slender, and in this form also the scales have more 

 numerous and longer cilia. The colours are brighter, and the under surface and sides 

 pinkish. 



A pale variety, having somewhat rougher scales with longer cilia, occurred between 

 tide-marks at Lochmaddy. 



The large arctic examples, such as those of Dr. Walker, have a distinct tendency 

 to elongation of the tips of the bristles, both dorsally and ventrally ; while a variety 

 from St. Andrews presents more elongated dorsal bristles than in the typical example. 



Few annelids are more abundantly distributed, yet the structural variation of the 

 individuals is not great. 



Habits. — H. iwibricata lurks under stones in pools and moist places between tide- 

 marks, among sponges and in their crevices, in tubes of Terebella and Chseiopterus, 

 in empty acorn-shells, and in almost any convenient crevice. It is one of the most 

 plentiful forms between tide-marks, and is also dredged abundantly in the laminarian 

 region and beyond it, in the crevices of old shells, tangle-roots, and stones. It clings 

 closely to such surfaces, and apparently tries to escape observation. Young examples 

 have been found in old shells with Polycirrus. It is most active and restless when 

 disturbed, and wriggles violently, leaving fragments of the body or separated scales in 

 the hands of the captor. 



It is a somewhat delicate animal in confinement. Thus it suffers rapidly in a 

 bottle with other marine animals on the collecting ground ; indeed, if the search be 

 prolonged few are alive, while other marine forms survive. Sir J. Dalyell, however, 

 retained them until the discarded scales were reproduced, being scarcely distinguishable 

 from the original scales in about six weeks or two months. It swims with an undu- 

 latory motion in the water, but, like the loach, soon sinks to the bottom. As in allied 

 species, it often strikes the glass vessels with its jaws, making sounds heard at a 

 considerable distance. 



It is brilliantly phosphorescent, discharging bright bluish-green or greenish scintil- 

 lations from the point of attachment of each scale, and thus under irritation the flashes 

 are arranged in pairs along the body or in a double moniliform line. The separated 

 scales also continue to gleam for some time, chiefly at the scar for attachment, that is 

 near the great ganglion of the region. If severely pinched it wriggles through the water, 

 emitting sparks of greenish or bluish-green light from the foregoing points. The phos- 



42 



