690 JAMES L, KELLOGG 
shown in figure 65, which represents the ends of several folds 
(fd,fd) near the ventral margin (vm). While the lower ends 
of the folds project for some distance ventralward, they are raised 
(iy 
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eeu — = 
NASUBUOUE rn pas) 
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Fig. 67 Yoldia limatula; ap, anterior palp; f, foot; g, gill; gm, suspending 
membrane of gill; lg, extension of lateral oral groove; pa, palp appendage; s, 
siphon; st, siphonal tentacle; vms, visceral mass. 
Fig. 68 Yoldia limatula; ciliation of gill and suspending membrane; cu, 
line of ciliary unions; gm, suspending membrane of gill; mp, modified plates of 
gills; pw, waste from palps; vec, ventral ciliated canal of gill. 
Fig. 69 Yoldia limatula; ciliation of ventral surface of gill; Letters as in 
figure 68. 
