2g6 OTT. [Vol. VII. 



of the indentation become continuous with the periphery of the 

 new pharynx at its anterior end. Here the epitheUal cells lining 

 the indentation come into contact with the cells of the pharynx 

 (Fig. 24, M). 



The anterior end of the pharynx next opens to the outside by 

 the separation from one another of the cells which lie between 

 its lumen and the bottom of the indentation of the integument. 

 This indentation of the integument persists as the cone-shaped 

 depression which leads to the mouth of the adult. The pharynx 

 remains in the condition stated above for some time, but at last 

 its lumen comes into connection with the lumen of the intestine 

 by the breaking through of the walls both of the intestine and 

 pharynx. This happens just before the bud separates from the 

 mother. While the budding is proceeding, the intestinal cells 

 of the bud are full of food material which has been taken in at 

 the mouth of the mother. In no instance was the bud seen to 

 take food through its pharynx while still in connection with the 

 mother. 



While the new pharynx is developing, the parenchyme cells 

 around it may be seen to be undergoing a differentiation. 

 Traces of new pharyngeal muscles and pharyngeal cells may be 

 seen surrounding the new pharynx (Fig. 24, P.M.). 



At the same time that these new organs are forming, the con- 

 striction of the body wall which separates the bud from the 

 mother gradually deepens until it touches the intestine. The 

 wall of the intestine also becomes constricted at the same time. 

 The intestine affords the last connection between the mother 

 and the bud. When the constriction of its wall closes this con- 

 nection, the bud fastens itself by its posterior end to some ob- 

 ject, and the mother, by a few quick contractions, separates 

 itself from it. The integument soon grows over the anterior 

 end of the bud and over the posterior end of the mother. The 

 integument at the posterior end of the mother continually grows 

 backward until a new tail is formed. The separation of the bud 

 from the worm is hurried if the worm is in any way irritated. 

 Sometimes under the pressure of the cover-glass, the worm may 

 be seen to divide, even though the newly formed organs of the 

 bud are not yet completed. In such a case both parts swim 

 about freely, and the organs of the bud are matured inde- 

 pendently of the mother. 



