1 62 T. H. MORGAN AND ALICE E. SCHIEDT. 



All the tail pieces show a new central pharynx and from two 

 to five new lateral pharynges. 



The second set of worms were cut into five similar pieces and 

 killed at the same time as the first set. 



Of the three head pieces (i.) and (iii.) show a new central and 

 four new lateral pharynges. 



(ii.) shows a central and three new lateral pharynges. 



The median pieces all have a new central pharynx growing 

 probably from the base of the old one. They all have several 

 new lateral pharynges ; and worms (ii.) and (iii.) have two lateral 

 old pharynges. 



Each of the middle pieces shows many old lateral pharynges. 

 (i.) shows one new lateral pharynx in the posterior end ; (ii.) 

 shows two new anterior and one new posterior pharynx ; (iii.) 

 and (iv.) show a new central pharynx and lateral ones anterior 

 and posterior. 



The posterior pieces (ii.) and (iii.) show a new central and new 

 lateral pharynx in the anterior part, old lateral ones in the middle, 

 and new lateral ones posteriorly. 1 (ii.) shows only a new central 

 pharynx ; the rest are old. Of the tail -pieces, (i.) has a new 

 central and five new lateral pharynges. In (ii.) no new pharynges 

 have regenerated. 



In (iii.) a new central and two lateral pharynges have devel- 

 oped. 



The third set, cut into five pieces, were killed twelve days after 

 the worms were cut. 



The three head-pieces show a new central and four new lateral 

 pharynges. 



Of the median pieces (i.) and (iii.) show an old central and 

 three new lateral pharynges. (ii.) has regenerated two new lat- 

 eral ones posteriorly; the four others, including the cential one, 

 are probably old ones. 



The new central and several old lateral pharynges are present in 

 the middle pieces ; new lateral ones are developed at both ends 

 of the pieces. 



Of the posterior pieces (i.) has one old and two new pharynges ; 

 the central one is not yet regenerated. 



*In this case it is probable that the cut removed some of the old posterior 

 pharynges. 



