16 Illustrations in British Zoology : — Aplidiiim nutans. 

 ]7. Afli'dium nu'tans. {fig. b.) 



A, The common masses of the natural size. B, An individual removed and magnified. 



Description, Common body adherent by a broad base, 

 knob-like or pear-shaped, nearly an inch high and half that 

 in diameter, smooth, gelatinous, pellucid, of a straw-yellow 

 colour tinted with brown, and marked with whitish streaks 

 from the immersed animals. There are no fibres nor spicula 

 to strengthen this common mass ; neither are there any visible 

 orifices on the surface ; but, by ripping up the skin with a 

 needle, the contained animals may be removed entire without 

 difficulty. These are of a long threadlike shape, with a 

 bulging and nutant head, scattered irregularly in the sub- 

 stance of the jelly, in which they lie horizontally or nearly so. 

 The length of a single individual is about four tenths of an 

 inch. The mouth {a) is cut into six equal segments, and 

 placed on the upper side of the large branchial sac (^), which 



