MELICERTADJE. 69 



are two moderate-sized gastric glands (PI. V. fig. '2'/, gg) in the usual position at the top 

 of the stomach ; and Mr. Gosse describes in M. ringens " near the tip of the foot on its 

 ventral side, a little granular body connected with the tip by a point, and enlarging at 

 the upper end where it is connected with a small globular vesicle." ' He suggests that 

 this is a foot-gland similar to that in so many other Eotifera. 



The Vasaular System. — The contractile vesicle is very small, and is generally hidden 

 by the viscera ; it lies close to the rectum. When the animal is viewed sidewise, the 

 lateral canals can be traced from a knot of twisted tubes in the shoulder to a similar knot 

 in the corona. Two vibratile tags can be seen at each knot. The lateral canals lie close 

 to the surface, and can be best found by slowly focussing upwards from any point near 

 the shoulder, and just under the cuticle. It is possible to trace them down from the 

 shoulder to the contractile vesicle; but it is not often that the viscera lying beneath 

 permit this to be done. 



The Reproductive System. — The ovary is similar in structure to those already 

 described ; it is somewhat oblong in shape, and extends between the stomach and ventral 

 surface, over nearly the whole of the latter. The oviduct passes beneath the intestine, 

 and in M . ringens " enters the cloaca near the point where the lower stomach [intestine] 

 opens into the excretory canal." 2 



The Nervous System and Organs of Sense. — The nervous ganglion has as yet only been 

 made out in M. ringens. M. Joliet (loc. cit. M. ringens) describes it as a group of big 

 cells of a very characteristic form, and provided with a large nucleus. Many similar 

 cells are placed beside the first, and stretch in different directions. It is not large, and 

 is situated on the dorsal face of the pharynx. The two ventral antennae (figs. 2c and 4, a) 

 are very obvious. Between them lies the buccal funnel, as well as the tract which, in 

 M. ringens and .1/. conifera, is engaged in forming and depositing the pellets ; and which 

 contains the chin (<■//), the ciliated cup (cc), and a prominent knob lying just under it. 

 The antennas are tubes, with a short transverse plug in them, carrying a pencil of delicate 

 seta'. This plug can be withdrawn into the tube at will, by a muscular thread; the top 

 of the tube itself following the plug, just as in a snail's horn. They are so situated that, 

 when Melicerta furls its corona, they stand on the top of the round closed head (fig. 

 lc, a). Immediately opposite to them, in M. ringens and M. conifera, there are two 

 curved sharp hooks ih), which look like weapons of defence; and between them lies the 

 third antenna, the dorsal one, which is nothing but a setigerous pimple. Two red 

 eyes are visible in the young, but none as yet have been seen in the adult. 



The Muscular System. — The longitudinal muscles, as in the Flosculariadce, run up the 

 foot to its junction with the trunk, where they are fastened. They then cross the trunk 

 till they reach the neck, where they are again fastened ; and as they reach the head they 

 divide into branches, which cross the lobes of the corona, and, by their contraction, furl 

 it. Transverse muscles, imbedded in the integuments, encircle the trunk ; and, by the 

 compression of the body-fluids, drive out and unfurl the corona, just as in Floscularia. 

 In II. conifera I have observed a set of longitudinal branching muscles, which are 

 inserted in the neck, just under the ciliated cup, and the prominent knob beneath it 

 (PI. V. fig. 2e, Im). It is by their varied action that Melicerta is able to curve and 

 twist its neck, and clinch its pellet on to the top of the tube, by the opposing pressures of 

 the knob and chin. 



The male has not yet been certainly recognised. I have seen what is probably the 

 male of M. tubicolaria, 3 and Judge Bedwell gives a graphic description of the probable 

 male of M. ringens,* and of its coquetting with the female ; Mr. Gosse has also seen what 

 there is little doubt was the male of M. conifera? 



' Quart. J. Micr. Scl. vol. i. 1853, p. 71, pi. ii. fig. 22. 



! Professor Williamson, Quart. J. Micr. Sci. vol. i. 1853, p. 1. 



• Sec p. 73 and PI, V. fig. 3c. ' Midland Naturalist, vol. i. 1878, p. 245 ; Bee also p. 71. 



5 Sec p. 72. 



