244 CTEXOPIIOR.E. Part II. 



whethor liy its own power or by the action of tlie vibratile cilia which line the 

 capsule it is not possible to say, as we have never seen the cilia in a quiescent 

 state. The narrow longitudinal area is a shallow furrow with a well-circumscribed 

 and somewhat prominent margin. The irregular transverse bulbs at the base of 

 its anterior and posterior halves, near the black speck, are the swollen extremities 

 of two branches of the medial vertical funnel. Starting from these facts, we may 

 perhaps throw some light upon the structure and functions of the Avhole structure. 

 Let us, for this purpose, consider anew the funnel itself "We have seen that it 

 is simply a central, vertical prolongation of the digestive cavity, tapering gradually 

 into a narrow neck ; but before it reaches the abactinal surfiice it enlarges again 

 very suddenh", branching into two forks, which are themselves swollen into two 

 irregular Indlis projecting towards the surface, one in front, and the other behind 

 the central black speck, but both close to it and partly encircling the tubercle 

 upon which the black speck rests. These two liulbs are therefore simple dilatations 

 of the forked abactinal extremity of the funnel, and we constantly see undigested 

 matters crowded in them and revolving in their cavity, with a tendency to accumu- 

 late laterally in an obliquely opposite direction in each of them. And at long 

 intervals these prominent oblique angles will open outward, when the fcecal matter 

 within the bulbs is discharged, the aperture remaining for a longer or shorter time 

 extended, and the vil)rating cilia lining the inner surface playing very actively ; 

 liut after a little while these openings shut again. 



These apertures might therefore be considered as a double anus ; but I think it 

 would be a very injudicious comparison to homologize them with the anus of higher 

 animals, for in this tj'pe the process of digestion and assimilation and the circu- 

 lation of the nutritive digested food are carried on by means of organs widely 

 difierent from those of either Mollusca, Articulata, or Vertelirata. We have seen 

 above, that the food is introduced into the digestive sac which occupies the centre 

 of the spherosome ; that this sac opens freely into the central chymiferous cavity, 

 anil discharges into it its contents, mixed with a large quantity of water ; that 

 this peculiar apparatus is sulyect to regular contractions, and circulates the fluid, 

 with the nutritive parts suspended in it, into the various tubes branching through 

 the whole system ; and that gradually the refuse matters accumulate on the aliactinal 

 ^prolongation of the central vertical funnel, to be discharged through the openings 

 of the two hollow bulbs branching from its extremity. We have here, therefore, 

 rather openings in the circulatory system than anal apertures ; or, rather, we have 

 here an apparatus entirely different in its adaptation from either the alimentary 

 canal or the circulatory s3-stem of higher animals, l)ut constructed upon the same 

 plan as similar organs in the class of Polypi and in other Acalephs, with only 

 this difterence, — that in Polypi the digestive central sac empties its contents into 



