ASEXUAL REPRODUCTION IN SAGARTIA 

 TABLE 2 



191 



No.l{^ 



No. 2{ I 



No. 3... 



No. 4.... 



REGENERATED MES- 

 ENTERIES 



d, ci 



d, cic2, c^c\ (1) 

 d, c^c^ 



d, c^c^, c^c*, d 



d, c^c-, c^c* 



OLD BOUNDING MES- 

 ENTERIES 



(1) 

 (1) 



Table 2 gives, in a form favorable for reference, the normal 

 regeneration formula of one side of the new area when the 

 adjacent old bounding mesentery is a complete non-directive, 

 c; an incomplete mesentery, (1); a directive, d; or when no un- 

 paired old bounding mesentery is present. The symbols used 

 are those adopted for the formulas of tables 3 to 8 (see explana- 

 tion, p. 232), except that the complete non-directive mesenteries 

 are numbered with exponent figures. Mesenteries represented 

 by the same symbol in different regenerating regions correspond, 

 in completeness or incompleteness, in location with respect to 

 the new directive plane, in position of the longitudinal muscle 

 bands, and, as will appear later, in size relations from a short 

 time subsequent to their first appearance until the new com- 

 plete mesenteries reach a degree of development equal to that 

 of the old mesenteries. It must not be assumed, however, that 

 the complete non-directive mesenteries designated by the same 

 exponent are in all cases homologous (cf. p. 197). 



When less than the maximum number of mesenteries repre- 

 sented in the above formulas are regenerated, two non-directives 

 on either or both sides of the new directives are commonly lack- 

 ing. The missing mesenteries are probably those designated c^ 

 and d. The reduced number is found in approximately 50 per 

 cent of all cases of regeneration following division in an endocoel 

 of the first incomplete grade, but rarely following division in 

 other planes. This is brought out in the right half of table 10. 



