(is; 



EXPLANATION OF THE PLATES. 



Fig. 2. A scyphojitoma-like process (f-j buckling fruiu 

 tlie basu of an old scyphostoma. 20 diametei-s. 



Fig. •". Two sc\pliostomas arising from a common basis. 

 20 iliamctcr.s. 



Fig. 4. An old scyphostoma, with largo otVslioots. 



Fig. 5. Similar to fig. 4, with one rigid-looking ofiVhoot. 



Finf. C. A scyphostoma bearing an offshoot with a glob- 

 ular tip. 



Fig. 7. A longitudinally ridged scyphostoma with a 

 distorted oll'shoot. 



Fig. 8. Here the otrshoot is ibrked {<" ,■'). 



Fig. 9. Tlie offshoots are remarkably long and ten- 

 tacular. 



Fig. 1". A strobila just making its first constriction. 



Fig. 11. A strobila with two coirstrictions. 



Fig. 12. A deformed strobila. 



Fig. 1.3. Two of tlie disks are well formed, but not 

 mature. 



Figs. 14 and 15. A foreshortened and a tlii-ee-quarters 

 view of the probo.scis of fig. 1 II. </ apertnre of the 

 mouth; < the sexiuil appendages. 20 diameters. 



Figs. IC and 17. Various attitudes of the proboscis of 

 fig. 2ij. a the cruciate aperture; o' lip; d cavity of 

 the proboscis; e sexual organs. 20 diameters. 



Fig. IS. jMore highly magnified view of the [iroboseis of 

 fig. 1 0. eruciatc fold of the lips »' ; h outline of 

 the ]iroboscis, in the distance; c inner surface of the 

 folds of the ajierture (/ ; c sexnal ajijiendages. (JO 

 <liameters. 



Fig. I'J. Lower side of an ephyra, a short time alter 

 it became free. The broad radiating canals J and 

 c occujiy as much sjiace as the intervals. 10 dianis. 



Fig. 20. Ujiper side of fig. ID when it is in a eiiu- 

 tracted state. 



Fig. 21. Same as figs. 19 and 20 when tlie nmlirclla 

 is reverted. 



Fig. 22. Profile view of an ephyra. which has the corners 

 {(i') of the lips and the veil {i') very prominently 

 developed ; P the tentacular lobe. 10 diameters. 

 Fig. 23. Same as fig. 20 in profile. .5 diameters. 

 Fig. 24. Another reverted form of fig. 19. 

 Fig. 2.J. Upper surface of an ephyra a little younger 

 than fig. 22. The branching lines are dorsal folds in 

 the canals. 10 diameters. 

 Fig. 2(5. Upper side of an ephyra, which is a little 



younger than fig. 2.".. About 1.5 diameters. 

 Fig. 27. A tln-ee-(pKu'ters dorsal view of fig. 19 in a 



reverted or diastolic state. f) diameters. 

 Fig. 28. Profile of fig. 19 in the diastole. 

 Fig. 29. Portion of the edge of an ephvra, bearing 



several tentacles and having an incipient lacunar 



branching of the canals. 

 Fig. ;)0. .Same as fig. 2.'), in a contracted state. 

 Fig. .-il. Oculiferous lobe of fig. 19, lower side. 2(> 



diameters. 

 Fig. 32. Dorsal view of fig. 22 in a contracted state. 

 Fig. 33. Foreshortened view of fig. .'51. 

 Fig. 34. Eye jiednnele of fig. 31. liO diameters. 

 Fig. 35. Cells from the upper surface of the lappet of 



the oculiferous lobe of fig. 25. nas.so-cells. 4 70 diams. 



PLATE Xlb. 



El'IIYlt.\ OF AHUELIA FI..\VI1>IT..\. 



[Drawn fium nature l>y II. ,1. Chirk.] 

 1 and 2, from an ephyra a little younger than that 



of fig. 19, PI. XI-->. 



. 1. The ineijiient sexual organ, seen from below, 

 with two rows of digitate a]ipendages, the longer ones 

 ((/) seen beyond the shorter. loo diameters. 

 . 2. The edge of the disc, seen from below, between 

 two ocidiferous lobes, bearing a single liudding tentacle 

 (('') and a tongue-shaped veil. ion diameters. 

 ;. 3. .Similar to fig. 2 but older, and belonging to 

 fig. 4. The principal feature is t!ie ineijiient folding 

 of the tentacular lobules r. 100 diameters. 

 . 4. Inferior view, from centre to margin, including 

 one of the oculiferous lobes and the two veils on each 

 side, of an ejihyra in which the radiating canals have 

 begun to branch ; a single tentacle has developed, and 

 the veil is half as long as the oculiferous lobes. 40 

 diameters. 



;. 5. Profile of an ephyra with thii'ty-two tentacles 

 at every interval. The disk is contracted ; the same 

 as fig. 20. Natural size. See PI. XI''. fig. 5. 

 ;. (J. .Shows the vibratile cilia on tlie inner suilace 

 of the proboscis of fig. 5. 5oo diami'ters. 

 ;. 7. The eye and eye pedimcle of fig. 4, seen froiu 

 below, to show the relation of the layer of the len- 

 ticular bodies of the eye to tlie walls. 50o diameters. 

 ;. 8. Longitudinal sectional view of the eye of fig. 

 7, showing that the lenses are in the inner wall. 

 ;'. 9. Liingitudiii.ll section of fig. 3, to show the re- 

 lations of the walls of the upper and lower floors. 

 100 diameters. 



;. 10. The sexual organ, with several rows of digitate 

 appendages, from figs. 17 and 18. \'icw t'roni below. 

 100 diameters. 



