AMPHITRITE. 247 
The animal sometimes reverses itself in its gelatinous dwelling, then 
remaining a short time with the head downwards ; and sometimes it 
forms an additional orifice above—therein shewing an analogy to the 
genus Terebella. 
It is surprising how such a diminutive creature can exhibit secre- 
tion so abundant in a definite form. Perhaps the exudation is from the 
whole body ; and it seems invariably concomitant on renewal of the sur- 
rounding element. 
Buoyancy is promoted by many air bubbles, which are especially 
about the orifice. If the tenant be vigorous, it is constantly there dis- 
playing its plume ; if weak and languishing, it hangs far out of the tube, 
like the preceding species. 
This is a timid animal ; it retreats suddenly for safety. Then, as 
well as during its return, it performs a partial revolution, the branchie, 
meanwhile, being closed as a spiral, whereby the entire plume resembles 
a screw of multiplied threads. Some weight may be thence allowed to 
Viviani’s characteristic Spirographus, as distinguishing the genus Am- 
phitrite. 
This, the Floweret Amphitrite, seems rare in the Scotish Seas. Only 
about six specimens have occurred to me, the last at the interval of 
seventeen years from those preceding it. None survived above four 
months. 
Pirate XXXI. 
Fic. 9. Amphitrite floscula. 
§ 4. MISCELLANEOUS. - 
Besides the preceding species, whose features are sufficiently defined, 
there are some other annulose animals which may be placed provision- 
ally im the vicinity of the Amphitrite. Farther observation will point 
out their precise position in the Systema if they ought to remain here. 
