HABITS OF THE OttTJPHlMl. 311 



I have been fortunate in finding it in the tubes of other 

 members of this family. 



Onwphis conchilega secretes a much flatter, elliptical, 

 transparent tube, which it protects with fragments of 

 bivalve shells, or flat stones, &c, thus forming a scabbard- 

 like structure, as shown in figs. 5 and 6. By carefully 

 dissolving away this outer covering with weak acid, I 

 have found the protective valves in this species also 

 (v, fig-. 7), though they are far more delicate than those 

 of Hyalinoecia. The end view of the elliptical transparent 

 tube and valves is shown by fig. 7a. The habits of this 

 worm are, moreover, exceedingly interesting in other 

 respects. Its tube is constructed of the shells, &c, 

 amongst which the animal lives, and consequently corre- 

 sponds so closely with the surrounding sea-bottom as to 

 afford splendid protection. 



In the British specimens from Liverpool Bay and 

 Plymouth which have come into my hands, the tubes have 

 varied in length from 1| to 3 inches, and in width from 

 J to J inch. Their anterior and posterior ends respectively 

 can generally be recognised, the former being terminated 

 with a larger overhanging shell or flat stone (a. fig. 5), 

 which completely hides the internal tube and its protective 

 valves, while at the posterior end (j 7 - $■§• 6) a scrap of 

 membranous tube can frequently be seen, covered with 

 mud or very small fragments of shell, &c, closing by 

 collapse upon the overlying shell. Each edge of the 

 sheath is protected by a little wall of sand grains, built in 

 between the flat sides, and keeping them apart. These 

 are clearly seen after treating a shelly-tube with acid, and 

 are shown at w, fig 7. The tube has also an upper (fig. 5) 

 and a lower side (fig. 6), the former being the one to which 

 the overhanging shell is attached, though there is reason 

 to think that the honour (?) is only temporary, and that as 



