Chap. I. 



REPRODUCTION OF CORYNE MIRABILIS. 



193 



Fig. 9. 



diverts its course, forming there a narrow cavity {Ficj. 2, c c^). At this early 

 period the medusa-bud has the power of extending and distending itself, to a great 

 length and breadth, so as to be at one time twice (PL XVIII. Fir/. 3) or thrice 

 as large as at other times. The simple 

 hernia-like state is soon superseded by 

 one which offers unmistakable evidences 

 of the medusoid nature of these buds (PI. 

 XVIII. Figs. 4, 5, G, and 7, and wood- 

 cuts 7, 8, and 9). Taking the simplest 

 view of this stage, at the plane of the 

 axis, as if the bud were split longitudi- 

 nally into halves, we may see that the inner wall (PI. XVIII. Fie/. 7, c) has reverted 



upon itself, and assumed a cup-shaped form, the hollow of 

 Avhich forms a close-fitting receptacle, or mould, as it were, 

 for the thickening [il^) of the under side of the outer wall. 

 By receding from this point of view, toward the surfece of 

 the bud (PI. XVIII. Fig. 5, and wood-cut 8), the rim {f) 

 of the cup comes into sight. In consequence of the re- 

 version of the inner wall upon itself, the cup naturally is 

 formed of a double layer {Fig. 6, wood-cut 9, c^ c-^, and 

 Fig. 7). In doubling upon itself, the retreating fold (c^) does 

 not press closely, at all points, upon the stationary one (c), but leaves four equi- 

 distant spaces, into which the chymiferous fluid penetrates. This gives the cup 

 a four-lobed appearance, each lobe {Fig. 4 and wood-cuts 1, c c^ (P' c^, and 8, c c^) 

 containing a chymiferous channel {ch). When seen from a jjoint opposite the 

 end of the bud, all four channelled lobes (wood-cut 10, c c^ <? e") 

 come into view at once, standing at four equidistant points, 

 ninety degrees from each other, around the cup. Between the 

 lobes, the wall {iw') is single, and, on account of the thickness 

 and dark color of the lobes, not easily recognized in profile, 

 but, as we have pointed out before, that part of it which helps 

 to form the edge {Fig. 5 and wood-cut 8, /') of the cup is 

 readily detected. In a view obliquely from the end, the rim 

 {Fig. 4 and wood-cut 7, / p f') of the cup, whether composed of a single or 

 double wall, is distinctly recognizable. Looking at the side of the bud, in a line 

 perpendicular to the outer surface of one of the lobes {Fig. 6 and wood-cut 9, c), 

 two others (c^) appear in profile, at a distance of ninety degrees from the first, 

 and the fourth one, on the distal side, at the same distance from the two in 

 profile. Advancing a little further, we find the channelled lobes (PI. XVIII. Fig. 8, 

 VOL. IV. 25 



