PLATE 9 



EXPLANATION OF FIGURES 



35 Diagrams T-VI, VIII, and X have been modified from those of Carlgren 

 ('09, p. 39, fig. II). Diagram VII has been constructed from his description 

 ('09, p. 35) of a si)ecimen of Sagartia viduata (no. 15a7). Diagram IX has been 

 taken from his figure ('09, Taf. 4, Fig. 47) representing a section of a specimen of 

 the same species. 



These diagrams show different arrangements of mesenteries found by Carlgren 

 in regenerating specimens of Sagartia viduata, Metridium dianthus, or Aiptasia 

 diaphana at stages giving indication of the order of development of the 

 mesenteries. 



Only mesenteries that would eventually be complete are represented. 



Portions enclosed in dotted lines represent old material. Some mesenteries 

 were present in every such region and, usually, one or more of the old mesenteries 

 were complete. The two mesenteries shown here are not to be understood as 

 indicating the number or character of old mesenteries. 



I have labeled the new mesenteries in one-half of each diagram I, II and III 

 with the symbols given in my figures and text to mesenteries occupying corre- 

 sponding positions with respect to the new directive plane. 



Carlgren's diagram 5 ('09, p. 39, Fig. II) shows mesenteries c- and c' on the 

 left side bearing muscles facing each other instead of facing the mesenteries 

 with which they commonly form non-directive pairs. The same arrangement is 

 represented on both sides in his figure 37 ('09, Taf. 3). Since I find no mention 

 in the text of so remarkable a condition, I am led to think that an error was made 

 in both places. I have therefore changed the positions of these muscles in the 

 corresponding diagram (III) of my figure. Certainly this coincides with the 

 conditions in S. luciae. 



For the frequency of these types of arrangement of mesenteries in regenerating 

 pieces of the different species, see table 12. 



For a discussion of the relations of these types, see text, page 201. 



36 to 41 Diagrams representing arrangements of orange stripes and white 

 bars, as seen on living specimens. The inner part of each diagram represents 

 the oral disc of an anemone with mouth in the center and with one or more white 

 bars, shown by stippled lines, extending radially across the disc. The tentacular 

 ring is not represented. In the outer part orange stripes are indicated by solid 

 lines. Broken lines mark the boundaries between recently regenerated and 

 older tissue. The distinction between these in living specimens showing early 

 stages of regeneration is indicated by differences in color; in length, width, and 

 density of the white bars; and in breadth, depth of color, and closeness of the 

 orange stripes. The newer area is toward the lower edge of the plate except in 

 figure 39, where it is above. 



36 Diagram of specimen at a stage of regeneration when all of the complete 

 mesenteries have formed but not all have reached the esophagus. A new white 

 bar but no orange stripes have appeared. A section of this anemone is shown 

 in figure 9. 



37 A specimen (no. 80, table 7) in an advanced stage of regeneration. Two 

 old and nine new orange stripes (the original record noted a possibility that one 

 of the mesenteries close to the boundary might be old). For a description of 

 internal structures, see page 211. 



(.Continued ora page S62) 



260 



