110 THE VOYAGE OF H.M.S. CHALLENGER. 



form eight separate bean-shaped glands, lying regularly distributed internally on the 

 subumbral wall of the coronal intestine, above the eight tentacles. More minute 

 investigation, however, shows that they are associated in pairs, as in the Cubomedusse 

 and Peromeduste. Consequently, there are really four interradial pairs of genitalia 

 present, which originally stood in immediate relation to the four septal nodes. We see 

 clearly, especially from transverse sections, through the proximal halves of the ovaries, a 

 little above the coronal muscle, that the eight genitalia really form four interradial pairs 

 which have been developed from the four interradial septal nodes. Each pair of genitalia 

 lies in a broad interradial pouch (br'), where the four interradial ocular pouches are still 

 united with their two tentacular pouches (fig. 4) ; and rather further down, the sterigrua 

 of the two associated genitalia are curved and rolled inwards in such a way that their 

 convex, lobed upper surfaces are turned towards one another. The two reproductive 

 glands of each pair consequently correspond to arched halves of the four interradial 

 genitalia of Tesserantha. The form both of the ovaries and the spermaria in 

 Nauphanta is bean-shaped or kidney-shaped, concave on the axial side, convex on the 

 abaxial. They extend above into the coronal sinus, near the septal nodes with the upper- 

 most parts of their truncated proximal half, whdst they almost touch the distal margin 

 of the coronal muscle and the tentacle basis, with the lowermost part of their thinner 

 distal half. The two halves are separated externally from each other by the proximal 

 margin of the coronal muscle (figs. 12, 14, mc), which stretches like a veil above the 

 lower balf. At a superficial view, it seems as if the genitalia lay in the subumbral wall 

 of the coronal intestine, and from thence form projecting pouches in the umbrella cavity. 

 Comparison of longitudinal and transverse sections shows, however, that for the most part, 

 they lie freely in the hollow space of the tentacular coronal pouches and are only con- 

 nected with their subumbral wall at a node-like point, which we shall call the genital root 

 (figs. 4-11, 15, st x ). The fulcral frame (" sterigma "), bearing the endodermal germinal 

 epithelium, runs out at this root from the gelatinous supporting lamella of the subumbrella. 

 The sterigma (st) or the fulcral frame of the genitalia runs out from the root as 

 a short, thick cone ; it immediately extends in the shape of a thin, strong, arched 

 shield, having many folds, and bearing numerous irregularly-formed hollow papillae on 

 its convex upper surfaee. This fulcral frame of the genitalium then appears branched 

 dcndritically both in the transverse and the longitudinal sections (4-11, fig. 15), it 

 corresponds to the pinnated genital rib of the Peromedusse ( " sterigma," p. 83, PI. 

 XXIII. fig. 38). The node-like root of the sterigma is crescentic, cut out concavely at 

 the upper or proximal margin. At the same time, it is hollowed out by a csecal arching 

 outwards of the coronal pouch, in such a way that in the transverse section (fig. 6) it 

 seems to begin with two separate radical branches, which are the two horns of the 

 crescent (st"). The shape of the sterigma is, therefore, really very complicated 

 (figs. 2-15). The cartilaginous connective tissue, which forms the fibrous stroma of the 



