BULLAA. 287 
margins sinuated. The body of this animal is therefore com- 
posed of an upper or head-lobe and the pedal disk; which, 
though their continuity is invaded as regards the integuments, 
are really integral plates from one extremity to the other. 
The lobes, as in Bulla hydatis, are separated by a deep canal, 
which, except for a very small extent, makes the circuit of the 
animal, less profound on the left than on the right side, from 
whence all the organs that are apparent without dissection 
may be observed; as the orifice of the verge on the right 
side of the head-lobe, the canal which is probably the vas 
deferens, or a continuation of it, the common receptacle of 
generation, the points of the branchiz, and the lateral leaflets 
on each side the mouth. To describe these organs would 
nearly be a repetition of the notes on Bulla hydatis; as 
they are essentially the same, the variations need only be 
mentioned. 
The branchiz, the common receptacle of the ova, &c., are 
placed more posteriorly here than in that genus. ‘The leaflets 
around the mouth between the groove, which I take to be 
salivary glands, are, as to general shape and position, similar 
to those in B. hydatis; their structure only differs, bemg 
composed of close-set, light brown vertical filaments or lines, 
the extent of which in depth is defined by the width of the 
canal, instead of bemg branched. The mouth is at the 
centre of the anterior part of the canal between the two lobes 
which assimilate in form about the buccal range, the pedal 
one more posteriorly expanding into fins or lateral lobular 
reflections; the fissure of the mouth is vertical. 
As to the internal organs of the present species, they are 
nearly identical with those of B. hydatis; the specialties are 
of the most trifling value; the ovary and serpentine oviduct, 
testis, the anus, the heart, auricle, vesica, coarse brown bran- 
chiz, liver and intestine, scarcely offer appreciabie variations. 
The mouth, as in B. Aydatis, is armed with a delicate folding 
masticatory apparatus, consisting in each jaw of about 12-15 
light-coloured, arched, pointed hooks curving inwards, sup- 
ported by a fleshy buccal mass, which terminates behind in a 
very short unarmed lingual riband. 
