10 
Fig. 7. 
Fig. 8. 
Fig. 9 
Fig, 10. 
Fig. 11, 
Figs. 12 
Fig. 14. 
"an 
an 
Fig. 
Fig. 16. 
Fig. 18. 
Fig. 19. 
BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
PLATE VII. 
Sense organ of Dactylometra quinquecirra, as seen from the oral side of 
the disk. 
Longitudinal section of the sense organ. opt, “olfactory” pit; con, oto- 
lythic concretions ; ect, ectoderm; ent, entoderm. 
Otolythic concretions from the sense organ of Dactylometra quinquecirra. 
Oral view.of sense organ of Dactylometra lactea. 
Section of immature egg from ovary of Dactylometra quinquecirra. 
and 13. Young scyphostome of Dactylometra quinquecirra, with two and 
four tentacles respectively. 
PLATE VIII. 
Longitudinal section of Dactylometra quinquecirra through the centre of 
two of the sub-genital pits. ge, gastric cirri; gpt, sub-genital pit. 
Plan of the stomach of Dactylometra quinqueeirra. r, 7’, 7, 7”, pockets of 
the stomach; rp, rp, radial partitions of stomach. 
PLATE IX. 
Dactylometra quinquecirra. 
View looking down upon a small portion of the genital organs to show 
gastric cirri (yc). 
View looking down upon one of the genital organs, the exumbrella being 
removed, and part of the genital epithelium being torn away in order to 
expose the opening of the sub-genital pit (gpt). 
Side view of oral fringes facing a primary radius. 
Aboral view of ocular lappets and tertiary tentacles. Showing the ten- 
tacle arising from a cleft in the lappet. 
Section 6.6u thick, through one of the red pigment spots of the exumbrella 
surface of the disk. The pigment appears as small highly refractive 
rosin colored granules in the protoplasm of the epithelial cells. Nema- 
tocystic capsules of various sizes are situated between the epithelial cells. 
An exploded nematocyst. 
A young and probably immature nematocyst exploded under the stimulus 
of picric acid. 
PLATE X. 
Dactylometra quinquecirra, 
Longitudinal section through edge of sub-genital pit and centre of one of 
the radial septe of the stomach. 
One of the wart-like protuberances of the exumbrella surface of the disk, 
showing pigment granules and clusters of nematocysts. 
Side view of oral fringes seen facing a secondary radius. 
View of ocular lappet and tertiary tentacle, showing a slight cleft in the 
lappet. 
Enlarged view of the tertiary tentacle shown in Figure 26, 
Oral view of primary tentacle. The tentacle is hollow. 
