EEPOET ON THE NEMERTEA. • 27 



out very conspicuously in the fresh condition of the animal, from being of the deep 

 burnt-sienna colour already mentioned. It consists of a broad, flattened mesial canal, 

 somewhat broadest in the middle region of the body, anteriorly ending in a bluntly 

 terminated cjecal prolongation, and posteriorly narrowing gradually. As the posterior 

 part of the animal was somewhat injured it could not be determined whether the canal 

 terminates in an anus or not. 



" The mesial canal receives on either side lateral tributaries in pairs, which tributaries 

 remain simple for some distance of their horizontal course, and then break up into 

 ramifications. The most anterior pair of lateral canals is split up into by far the most 

 ramifications. The ramifications become less and less in each pair towards the posterior 

 extremity of the body, some of the most posterior lateral canals being simply bifurcate, 

 and one merely enlarged at the extremity. There are thirteen pairs of lateral canals 

 in all. 



"The nervous system was plainly seen in part. A pair of rounded ganglia lie on the 

 ventral and lateral surface of the sheath of the proboscis, being a little posterior in position 

 to the mouth. A commissure passes above the oesophagus and between it and the 

 proboscis-sheath. From the ganglia a pair of fine simple nerve-cords pass in a curved 

 course dowai to the posterior extremity, where their termination could not be ascertained. 



" The cords cross ventrally the lateral digestive canals about the point where 

 ramification commences. Further connections of the ganglia could not be ascertained. 



" The specimen obtained was a female. A series of ovaries, consisting of pear-shaped 

 masses of minute ova, were present, situate between each of the pairs of lateral digestive 

 tubes immediately external to the nerve-cord on each side. The masses of ova are 

 contained in small cavities in the gelatinous internal body-tissue. When pressure was 

 exerted the ova issued from small corresponding apertures on the ventral surface, and the 

 small empty cavities remained. The ova were spherical, about "28 mm. in diameter, and 

 appeared composed of fat-globules and granular matter. 



" The proboscis-sheath, which is wide and capacious, is very plainly seen on the dorsal 

 aspect of the body, and dimly through the thickness of the body from the ventral aspect. 

 It has a firm muscular attachment at its orifice, and bundles of muscular fibres (apparently 

 retractor) are attached to it here on either side (pi. xv. fig. b, 1 = PL I. fig. 24). The 

 proboscis itself is, when retracted, coiled up in the usual manner within its sheath, as 

 seen in fig. D ( = PI. I. fig. 25). It could, unfortunately, not be ascertained whether the 

 proboscis is armed or not. It was never entirely retracted, but a small portion of it always 

 remained exserted. 



" The outer surface of the body of the Nemertine is covered with a hyaline, very thin 

 integument, which is thrown into numerous folds and wrinkles, which are so arranged 

 along certain lines around small spaces nearly free from them as to produce on the surface 

 of the body an appearance of a series of small polygonal areas, separated by fine reticular 



