PLATE II. 



The lettering is the same in aU the figures. 



a Acontia. 



b Mesenteric filaments. 

 c Stomata in the septa. 

 c 1 Perioral stomata. 

 c - Marginal stomata. 

 en Cuticle. 



d Glandular streaks of the mesen- 

 teric filaments. 

 t Ciliated streaks of the mesenteric 

 filaments. 

 Ectoderm. 

 Endoderm. 

 Reproductive organs. 

 Septa, rh Directive septa. 

 Oral disk. 



ek 



k Wall. 

 I Pedal disk. 

 in Muscles. 

 mm Mesodermal muscles. 

 ml Longitudinal muscles of the septa. 

 ■ml 1 Retractor. 

 inp Parietobasilar muscle. 

 int Transverse muscles. 

 mr Radial muscles of the oral disk 

 and longitudinal muscles of the 

 tentacles 

 vis Circular muscle of the wall. 

 me Mesoderm. 

 11 Urticating cells. 

 o Ovicells. 



p Filamental apparatus of the ovicells. 

 p 1 Process of the ovicell. 

 p 2 Apical set of epithelial cells. 

 r Marginal spherules. 

 rh Directive septa. 

 .9 (Esophagus. 

 so Openings of the oesophagus into 



the radial chambers. 

 sr (Esophageal grooves. 

 sz Lappets of the cesophagu-;. 

 t Tentacles and the openings homolo- 

 gous with 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 



Oc. 1. Oe. 2. 



D 195 240 



F 410 550 



J 470 580 



A with unscrewed front lens ('inser. A) magnifies with Oc. 1 : 30 times ; with Oc. 2 : 40 times. 



a 1 

 A 

 C 



Oc. 1. 



6 



55 



95 



Oc. 2. 

 10 



70 

 125 



Fig. 1. Corallimorphus rigidus, seen from the oral disk ; one half the natural size, 



Fig. 2. Corallimorphus profundus, seen from the pedal disk ; one half the natural size. 



Fig. 3. ,, ,, seen from the oral disk ; one half the natural size. 



Fig. 4. Lateral view of a portion of Corallimorphus rigidus ; natural size. 



Fig. 5. Half of the pedal disk of Corallimorphus rigidus ; natural size. 



Fig. 6. A septum with two tentacles, running out from the corresponding intraseptal 

 .-pace ; seen from the side of the intraseptal space. 



Fig. 7. Polysiphonia tuberosa, 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. Sphenopus arenaceus, bisected longitudinally ; natural size. (By an oversight 

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



Fig. 11. Poly o pis striata, twice the natural size. 



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



Fig. 12, b. Bunodes mi until, bisected longitudinally. 



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

 oral disk. 



