48 HIRUDO. 
frequent disparity in the dimensions of all soft animals ; and it was rather 
languid and contracted. Its eyes did not appear round, but somewhat 
irregular under the microscope.—Fig. 12, 
The ova were expanding to vivid yellow young on the 234d, all still 
adhering to the belly of the parent.—Hig. 14 enlarged ; a cluster of ova 
more enlarged, fig. 15. 
In two days longer, they seemed to be very deeply indented by a 
number of segments, and some as if a deep cleft had been received in 
front, though these appearances subsequently proved illusive. The 
young animals were slightly curved, and they lay close together. I 
rather impatiently expected them to be free in a few days, for they did 
not admit of convenient observation. 
Allthe young were still 7v situ applied to the belly of the parent on 
the 28th of July ; several were liberated on the 29th. 
The indenting segment had been computed as containing twelve or 
thirteen. But it was now evident, from the free application of the micro- 
scope, that the supposed annulations or segments, were thirteen pair of 
ventral sacs within the integument of the body, and exposed by its trans- 
parence ; farther, that the supposed cleft was only an interval near the 
sucker. Likewise, the yellow colour plainly resulted from the contents 
of the sacs ; and it was further discovered that the young animals had red 
eyes. 
A favourable opportunity occurred of inspecting one which had 
quitted the parent, when it appeared that adhesion to the belly is not 
by the sucker, which is very large, but too weak to be effectually used 
for some time; that the red eyes are very conspicuous ; and that the 
contents of the ventral sacs are speedily dissipated when they appear in 
greater number, as if composed of smaller compartments.—Fig. 18, en- 
larged ; more enlarged, fig. 19. 
Thus a tolerably connected series of observations on the yellow 
leech was obtained, though some important points of its history still re- 
main for elucidation. 
The animal is rare. 
