FLOSCULARIAD/E. 01 



setae arc far longer than they appear at first sight, and are not stiff bristles as Ehrenberg 

 has drawn them, but are gracefully curved, and taper off into lines of exquisite fineness. 

 Those of one arm interlace with those of the arms on either side of it, so as to form a 

 living cage of the finest network, through which it is hardly possible for anything to 

 pass without striking some part of the sensitive meshes. The instant this happens band 

 after band of the setas lashes at the runaway, a swift wave of motion runs along each 

 band, and the captive is thrown back into the vortex produced by the wreath at the 

 bottom of the coronal cup, the ciliary armature of which is precisely like that already 

 described in Floscularia. I have also on more than one occasion detected a fitful ciliary 

 wave running round the top of the coronal cup, just under the level of the lowest points 

 of the depressions between its lobes'. This has not hitherto been noticed, but I am 

 certain of the fact : the motion was of the briefest duration. 



There are considerable differences of opinion about the muscular system. Dr. Leydig 

 (loc. cit.) says that there are four muscles which rise in the foot, and each of which divides 

 into a pair, as it crosses the trunk, and then subdivides into smaller branches, as it passes 

 over the coronal cup to the base of the lobes. Mr. Gosse makes them to be five pairs, 

 and says that usually each pair runs up the trunk from the foot in a line with one of the 

 arms ; and then, before reaching it, divides into diverging branches which, at remote 

 points, are united to a muscular collar close to the base of the arms. He notices, how- 

 ever, that he has seen cases where the muscles run down direct from the depressions 

 between the lobes without uniting to form pairs. 



My own opinion, after prolonged observation of many specimens, is that there are 

 really six pairs of muscles, and that they are arranged in the following fashion. Each 

 pair runs up the foot looking like a single muscle ; and the reason why never more than four 

 (pairs) are visible in the foot from any point of view, is that there is always a pair on 

 each side of the animal (however viewed) which is there lost to sight. At the junction 

 of the foot and trunk each pair begins to open a little ; and by the time they have reached 

 the bottom of the coronal cup the constituents of each pair diverge obviously from each 

 other, and terminate usually at the base of some one of the depressions between the 

 lobes : but in such a fashion that the constituents of the same pair never end in the 

 same depression (PI. IV. figs. 2, 3, 4, lm). There is, however, an exception to this in 

 the case of the two pairs of dorsal muscles (PI. IV. fig. 2, lm). Here it will be seen 

 that while the outer muscles in each pair end in a depression between the lobes, the 

 inner muscles curve over towards each other and meet so as to form a fine arch, some 

 distance below the base of the dorsal lobe. There are, too, fine hexagonal markings 

 visible on this side of the coronal cup, which are probably the boundaries of large cells : 

 oval nucleated cells are also easily seen in the wall of the coronal cup, when the animal 

 is viewed from either side (fig. 4). 



The nutritive and reproductive systems are so similar to those of Floscularia, that 

 they require no separate description. It is enough to call attention to Dr. Leydig's 

 figure of the ovary treated with acetic acid (reproduced in fig. 7), and exhibiting the ova 

 in various stages of growth, as well as its own delicate walls, and the oviduct (ot), which 

 leads into the cloaca (cl). 



The Secreting System. Neither salivary, gastric, nor foot glands have been observed 

 in Stcplianoceros, but as the animal secretes a large and comparatively solid tube, it is 

 clear that it must either have some organ for this purpose, or that i<he substance of 

 which the tube is constructed oozes from the surface of the body. 



The vascular system is much better seen in this genus than it is in the preceding. 

 Fig. 4 shows Stcplianoceros viewed a little obliquely from the side on the left of the 

 dorsal surface. The left lateral canal (fig. 4, Ic) can be seen winding to the left of the 

 nervous ganglion (gn) and having two vibratile tags (vt } , rt. 2 ) attached to it close to where 

 the left eye (e) is. The lateral canal then divides into two branches ; the right branch 

 curving upwards towards the dorsal surface to meet its fellow on the median dorsal line 

 (see fig. 2), while the left branch passes along the side of the vestibule till it nearly 



