226 \YINTERTON C. CURTIS. 



PLATE VI. 



Figures showing the development of the " long-necked " specimens of C. lacinia- 

 tum. All from camera lucida outlines. The magnification is given for the figures as 

 reproduced. 



FIG. 15. A "long-necked" specimen in which the reproductive organs can be 

 made out as far forward as the fifth proglottid. The tenth and last is about ready to 

 be shed. < 12 diameters. 



FIG. 16, a and b. The entire length of a specimen which is approaching the 

 "long-necked" condition. There is a total of 98 segments and the reproductive 

 organs can be distinguished as far forward as the twenty-sixth proglottid. X I2 

 diameters. 



FIG. 17. A "long-necked" specimen with 8 of the old anterior proglottids and 

 the new segmentation begun in the posterior region of the neck. >< 12 diameters. 



FIG. 18. A "long-necked" specimen in which the new segmentation has not yet 

 begun. X I2 diameters. 



FIG. 19. A "long-necked" specimen with an unsegmented zone further back. 

 See text for a possible explanation of this specimen. x[ 12 diameters. 



FIG. 20. A "long-necked" specimen which has still 49 of the old proglottids in 

 which reproductive organs can be made out as far forward as the third or fourth from 

 the anterior end. The neck region has begun to segment at either end. X I2 

 diameters. 



