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 23d, all still 

 adhering to the belly of the parent. Fig. 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. 



All the young were still in 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. 



