130 DESCRIPTION OF THE PLATES. 



way betvveoa its two ends. Remarkable for the horse-shoe form of the section of the hollow musele 

 (r), as in the last figure {fig. 127, r). 



Fig. 129 (350 diam.). Portion of a space between two adjoining peduncular tubes {fig. 128), show- 

 in" the irregular form and granulation of the young Cbrilloe (c^) in the homogcneeus cjtoblastema 

 of the choudrophys. 



PLATE XI. Figures 130 to 145. 



Fifjs. 130, 131, 132 (1050 diaiu.). Spermatic particles at the niomeut of escape from the genital 

 sac. 



Figs. 133 to 141. Larger kind of neraatocysts from the tentacles, in various degrees of aversion, 

 or at rest. Figst. 138 aud 141, of diagramatic size, and the rest, from^^y. 133 to 140, magnified 1050 

 diameters. Fig. 133. Not fully grown nematocyst, closed. A part of the coil omitted to expose 

 the central shaft {d). Fig. 134. Fully developed cyst, but not the largest, closed. A sectional 

 view, the coil in the distance {Ic). Fig. 135. The basal half of the shaft {bl) everted. Fig. 136. 

 The whole shaft {hi, dl) everted. Fig. 137. The whole shaft (bl, dl) and a part (A) of the hollow 

 thread everted. Fig. 138. Partly everted thread, showing the manner of its sliding within itself 

 Fig. 139. A completely everted cyst, showing the spiral rows of bristles on the shaft and the 

 twisted triangular thread {tl). At D, the blunt tip of the thread. Fig. 140. The end of a shaft 

 rapidly tajiering into the thread after eversion. Fig. 141. Diagramatic view of the base of the thread, 

 showing the spiral course of the edges of the twisted trihedral, and the abrupt termination of the 

 rows of setiB of the shaft. 



Figs. 142 to 145. The smaller nematocysts, from the tentacles (1050 diara.). Fig. 142. Fully 

 developed cyst, closed. The coil partly omitted, not to confuse the connection of the shaft {si) with 

 the thread. Fig. 143. View from the sid(! opposite to the one seen m'fig. 142, showing the U;rm\- 

 nation {Ic) of the thread, and its mode of coiling. Fig. 144. View at ninety degrees from that of 

 fig. 143. Fig. 145. The thread totally everted. 



