NEMERTEANS. 109 



Fragments of two specimens preserved, i.e. about 73 mm. of one worm and 98 mm. of 

 a somewhat smaller specimen. The latter specimen is almost complete. The breadth is fairly 

 uniform, being about 2'5 mm. in the larger and 2 mm. in the smaller specimen. The intestinal 

 region is somewhat flattened, though not greatly so. The head is sharply pointed, the head 

 slits are long, and the mouth is long and slit-like. Colour when alive white or whitish 

 flesh. 



The epithelium is somewhat low and contains a large number of unicellular oral glands. 

 It rests on a thick basement membrane (PL V. fig. 2) beneath which is a well-marked layer 

 of circular muscle fibrils. Between this layer and the outer longitudinal muscle layer is the 

 cutis, which contains a few small bundles of longitudinal muscle fibres, traces of cutis glands 

 and a little connective tissue. 



The muscles of the body wall are fairly well developed. The outer longitudinal layer is 

 about double the thickness of the circular layer (PI. IV. fig. 9) in the oesophageal region, and 

 this again is twice as thick as the inner longitudinal layer. The oesophagus is provided with 

 a separate and very delicate coat of longitudinal muscles. There is a strong layer of horizontal 

 muscles over the mouth. 



The mouth commences at the level where the cerebral organ terminates, or slightly in 

 front of that level. The intestine possesses a well-marked ventral gutter. The hinder part of 

 the oesophagus is much constricted. 



In the vascular system there is present a cephalic loop. Shortly behind the termination 

 of the excretory tubules the oesophageal lacunae are gathered into a single lacuna, which later 

 becomes the lateral blood vessel of the intestinal region as in C. maldivensis (p. 107), C. macu- 

 latus (p. 108). The dorsal blood vessel leaves the proboscis sheath at the level where the 

 oesophageal lacunae are gathered into a single lacuna, i.e. rather more than 1 mm. behind 

 the termination of the excretory tubules. The arrangement of the blood lacunae in the cere- 

 bial region conforms to the typical Lineid type. 



The proboscis is long and fairly stout, being about 1 mm. in diameter. It presents the 

 usual three muscle layers and possesses two muscle crosses. 



The excretory tubules first appear in section just before the posterior limit of the mouth. 

 They extend a little way dor.sally and ventrally to the level of the nervous stems. In one 

 specimen there was a single duct on either side, making an angle of about 45° (PI. IV. fig. 9, 

 exd.) with the nervous side stems. In the other specimen there was a single duct placed 

 rather in front of the middle of the system on the right side, whilst on the left side there 

 were four ducts, the most anterior of which had almost disappeared. 



No gonads were found in either specimen. 



The brain is large and the dorsal ganglion is more than double the size of the ventral. 

 The median dorsal nerve is not well marked. Neurochord cells occur on the inner side of 

 each ventral ganglion shortly before its separation from the dorsal ganglion. The median 

 dorsal nerve is not well marked. The cerebral organ is large (PI. V. fig. 4 c), and the gland 

 cells in connection with it are somewhat scanty. The head slits are deep, reaching almost to 

 the brain. At the same time they are exceedingly wide. They continue deep after the ciliated 

 canal has been given off, and terminate at a level slightly behind the posterior end of the 

 cerebral organ. 



