L U C E 11 N A R 1 .E A N D T II E I R A L L I E S . 53 



spherical, nematocystigerous tip to an equally well-proportioned shaft. If the 

 broad median furrow {fi(j. 2t, a'') of the anterior face of the; ovate mass, be followed 

 outwardly toward the distal end, it will be noted that it gradually becomes less 

 opaque tlian the area adjoining, and finally assumes a semi-transparent appearance 

 for a short distance before it terminates. In the middle of this semi-transparent 

 area {fi(j. 25, a*) there is a dark spot, which some observers in their haste have 

 mistaken for an opening, supposing the darkness to be the pigment mass lining the 

 interior of the cavity of this body. So far, though, from being thus, the dark spot 

 is not only the surface of a solid, but that solid is slightly elevated above the area 

 in which it is set, as one may see by glancing along the furrow, when it will appear 

 as a spheroidal mass (a") imbedded on the top of a low boss, or truncate cone. 

 Here again we meet with the striiE noticed on the neck, but not so strongly marked, 

 yet sufficiently distinct to be traced along the semi-transparent area and upon the 

 boss to the margin of the spheroidal mass. We hardly need say that the latter is 

 the homologue of the globose tips of the tentacles. In extremely old animals the 

 boss, even, is obliterated, and the spheroid is sunken into the face of the semi-trans- 

 parent area, but is still distinctly recognizable by tlie numerous ncmatocysts which 

 are embedded in its substance {fg. 47, a^). It is not then the globose tip of the 

 tentacles that we find here metamorphosed into an immense ovate, swollen mass, 

 but a part of the shaft lying intermediate between the base and the end of it. 



107. Keeping in mind, now, that the stem is attached obliquely to the broader 

 end of the ovate mass on its posterior side, and that the spheroidal tip has been 

 found at its narrower, distal end, and on the anterior face, we are prepared to 

 luiderstand that this mass trends obliquely to the longer axis of the whole, /. e., 

 the shaft, and completely encircles it in the form of a thick, broad, ovate, pad-like 

 ring. The breadth and depth of this mass is not altogether d>ie to the thickness 

 of the ovate ring, but is in part accounted for by the very considerable extent of 

 the cavity (.AV- ^^5 "0 of this organ, occupying not less than one-third of its 

 diameter. Like the tentacles, the anchors are capable of expansion and contraction, 

 but not to as great a degree. In the common run of adult specimens they are 

 slightly knobbed or have an midulating outline, but in the very old ones they are 

 deeply puckered, as if shrivelled, reminding one of a dried prune or raisin. Their 

 color and opacity are the result of the combination of two distinct sets of pigment 

 matter ; the one lying near the surface, constituting the large, dark nuclei of the 

 cells of the outer wall, and the other seeming to form a layer on the interior face, 

 but in reality embedded in tli(> lining wall, occupying in it the place of nuclei of 

 the cells. The adhesive vesicles (^ 208, A) which are buried just beneath the ex- 

 terior surface add a little to the opacity ; but being colorless, they are not conspicu- 

 ous, notwithstanding their large numbers. 



108. It is no difficult matter to expose the entrance {Jhj. 45, a^) to tlie cavity 

 of the anchor and at the same time prove that it has, like the tentacles, an open 

 communication with the wide chambers of the umbella. There are no interten- 

 tacular, internal lobules here to obscure the view, and if one wishes to verify, by 

 the tactile method, wliat has bc»en ascertained with the eye alone, it can be readily 

 done by cutting and raising a fiap of the anterior parietes of the umbella, so as to 



