PLATE II. 



The lettering is the same in all the figures. 



a Aoontia. 



b Mesenteric filaments. 



c Stomata in the septa. 

 c ' Perioral stomata. 

 c ^ Marginal stomata. 

 cit Cuticle. 



d Glandular streaks of the mesen- 

 teric filaments. 



e Ciliated streaks of the mesenteric 

 filaments. 

 ek Ectoderm. 

 cii Kndoderra. 



g Reproductive organs. 



h Septa, rh Directive septa. 



i Oral disk. 



k AVall. 

 I Pedal disk. 

 m JIuscles. 

 mm Mesodermal muscles. 

 7nl Longitudinal muscles of the septa. 

 ?ftP Retractor. 

 mp Parietobasilar muscle. 

 7>U Transverse muscles. 

 mr Radial muscles of the oral disk 

 and longitudinal muscles of the 

 tentacles 

 ins Circular muscle of the wall. 

 7fte Mesoderm. 

 n Urticating cells. 

 Ovicells. 



p Filamental apparatus of the ovicells. 

 p^ Process of the ovicelL 

 p'^ Apical set of epitlielial cells. 

 »• Marginal spherules. 

 rh Directive septa, 

 s CEsophagus. 

 so Openings of the cesophagus into 



the radial chambers. 

 sr (Esophageal grooves. 

 sz Lappets of the cesophagus. 

 t Tentacles .and the openings homolo- 

 gous ^vith them. 

 t ' Principal tentacles. 

 t ^ Accessory tentacles. 

 V Openings of the pedal disk. 



All statements given as to magnifying powers have reference to Zeiss's system. The magnifying powers amount to 



a' 

 A 

 C 



Oc. 1. 

 6 

 55 

 . 95 



Oc. 2. 



10 



70 



125 



D 



F 

 J 



A with unscrewed front lens ('inscr. A) magnifies with Oc. 1 



Oc. 1. 



195 



410 



470 



30 times; with Oc. 



Oc. 2. 



240 

 550 

 5«0 



; : 40 times. 



CoraUimorphus rigidus, seen from the oral cli.sk ; one half the natural size. 

 Corallimo^phus profundus, seen from the j)eclal disk ; one half the natural size. 

 ,, ,, seen from the oral disk ; one half the natural size. 



Lateral view of a portion of CoraUimorphus rigidus ; natural size. 

 Half of the pedal disk of CoraUimorphus rigidus; natural size. 

 A septum with two tentacles, running out from the corresponding intraseptal 

 space ; seen from the side of the intraseptal space. 



Fig. 7. Polysiphonia Uiherosa, lateral view ; natural size. 



Fig. 8. Polysiphonia tuberosa, a part of the margin of the oral disk, the tentacles 

 having been cut away at their bases. 



Fig. 9. Polysiphonia tuberosa, seen from the oral disk. 



Fig. 10. ;S^j/ie?iC»pi/.s arenaceifs, bisected longitudinally ; natural size. (By an oversight 

 the microseptum has been omitted on the left-hand side.) 

 Fig. 11. Polyopis striata, twice the natural size. 

 Fig. 12, a. Bunodes minuta, natural size. 

 Fig. 12, b. Bunodes minuta, bisected longitudinally. 



Fig. 13. Stephanactis abyssicola, one and a half times the natural size ; seen from the 

 oral disk. 



