upon tbe Structure and Oeconomy of Tania. 255 
which croffes halfway over the body of the joint, and then turns 
downwards; here it ends, and does not communicate with any 
of the neighbouring veflels, as I have found by repeated injec- 
tions. | 
"The ufes of thefe ofcula feem firft to be that of fuckers or tenta- 
cula, for attaching the long body of this animal to the inner coats. 
of the inteftines; I have feen them ferving this office, and it ap- 
pears that the external lips and cup are chiefly employed in it. 
The fecond ufe of the ofcula appears to be fubfervient to gene- 
ration; and the canals, fee fig. 6. feem to be the oviducts. Ina 
Tenia of this fpecies, which I obtained before it was dead*, I ob- 
ferved at one part where it had formed a knot upon itfelf, that 
two pairs of thefe ofcula were in contact with each other, and were 
agglutinated together by a vilcid mucus. I was not at that time 
aware of the poflible RER of this conoci and neglected pre- 
ferving them. ftate. I now fufpeé, er, that they were: 
in the act of copulation, and thgt a mutual influence takes place 
previous to the formation of ova. From hence it appears that 
each joint is an individual, yet dependent upon the head and 
other parts for its fubfiftence, the means of propagation being as 
much in the power of every joint as it is in the power of a com- 
mon fnail, which is an hermaphrodite. 
The chance of an ovum being placed in a fituation where it 
will be hatched, and the young find convenient fubfiftence, muft 
be very {mall; hence the neceffity for their being fo prolific. 
If they had the fame powers of being prolific which they now 
have, and their ova were afterwards very readily hatched, then. 
the: multiplication of thefe animals would be immenfe, and be-. 
come à nuifance to the other parts of the creation. 
* From a young woman in Hermitage-ftreet in the year 1789.. 
Another 
