AGASSIZ AXD WOODWORTH : VARIATIONS IX EUCOPE. 149 



Fig. 5. Female with five radial canals, one of wiiicli forks at the periphery, and 



five very unequally developed genitals. 

 Fig. 6. Male with five radial canals, unequally developed genitals, and segments 



of unequal size. 



PLATE VI. 



Fig. 1. Male Eucope with five radial canals, one of which forks above the genitals 

 close to the base of the digestive cavity, dividing the disk into six 

 different-sized sectors. 



Fig. 2. A male Eucope similar to Figure 1, with more fully developed genitals. 



Fig. 3. Young Mnemiopsis Leidyi A. Ag., magnified ^. 



Fig. 4. Doliolum sp. in profile, magnified ^'j^. 



Fig. 5. Annellid larva ( Aricidea ?), magnified ^^. 



Fig. 6. Ectopleura ociiracea A. Ag., seen in profile, magnified ^. 



PLATE VII. 



To illustrate the formation of spurs, branches, and anastomosing canals from the 



sides of the radial canals. 



Fig. 1. Slightly projecting spurs on side of radial canal. 



Figs. 2, 3, 6, 7, and 10 show quite prominent hook-like lateral prolongations from 



the sides of the radial canals. 

 Figs. 4, 5, and 9 show forks of the radial canals in Figure 4 above the genitals, in 



Figure 5 below. 

 Fig. 4 shows a transverse canal connecting adjoining radial canals. 

 Fig. 8 shows a circular canal connecting the radial canals below the base of the 



manubrium. 



PLATE VIII. 



Fig. 1. Marginal sense-bearing tentacle with three otoliths. 



Figs. 2 and 3 show the coalescence of adjoining marginal tentacles. Figure 2 with 



one otolith. Figure 3 with two. 

 Figs. 4-13 show the mode of formation of an abnormal basal spur frequently 



seen jutting out from the marginal tentacles, either with or without 



otoliths. 

 Figs. 14-17 show the numerical variation of the otoliths in the sense organ of the 



marginal tentacle. 

 Fig. 18 shows the coalescence of male genital organs of adjoining radial canals. 

 Fig. 19 shows the formation of a radial canal shooting up from the circular canal. 

 Fig. 20. An abnormal Eucope with confluent radial canals and ovaries developed 



on the main and the lateral canal. 

 Fig. 21 shows lateral leaf-like expansions of male genital organs which have not as 



yet run together, as in Figure 18. 



