130 "TE1IRA NOVA" EXPEDITION. 



EXTERNAL FEAT u RES. 



The cliic'f points in the external appearance of L. xeutti which serve to distinguish 

 ii fro in TJ. rarriti/itfitx are as follows: 



The skin is comparatively smooth, and not thrown into marked wrinkles and 

 furrows. 



The head is usually blunt arid rounded in front. The siiout is, however, evidently 

 capable of some extension, as in a small number of individuals it has been fixed in a 

 more tapering form. 



The young specimens do not appear to coil up veutrally in a spiral when killed, 

 as do those of L. <-t'ni<jatiin. 



The mouth (PL II, fig. 1) is a longitudinal slit, but not nearly so elongate as in 

 the other species. In the largest individual it measures 5 mm. in length. The 

 lips are thrown into regular folds transversely to the loua; axis of the mouth. 



O i/O 



There is in many cases a more or less well-marked transverse groove behind the 

 cephalic, slits. This is especially noticeable on the ventral side (PI. II, fig. 1), where 

 it runs back in the middle line to meet the anterior end of the mouth, thus forming a 

 V-shaped furrow. 



The cephalic slits are very deep and clean-cut, measuring about 4 mm. in length 

 in the largest individuals. 



The proboscis-pore (PL II, fig. 1) is, as usual, a vertical slit at the tip of the 

 snout, crossing at right angles a slight groove which joins the anterior ends of the 

 cephalic slits. 



In length, complete specimens (of which there are few) measure from 2 ' 4 cm. to 

 10 '7 cm. The larger specimens are all fragmentary, and it is impossible to guess at 

 the maximum length probably attained ; but this would seem to be certainly very 

 much smaller than that reached by L. eornigattix. In thickness, the largest fragment 

 measures about 8 mm. laterally and 6 mm. dorso-veutrally ; the other specimens vary 

 greatly in thickness according to their state of contraction. 



No traces of the original colours of the species can lie made out. 



Nearly all the specimens appear to be sexually immature. 



INTERNAL ANATOMY. 



l)inli/-irnll. The outer epithelium (PL II, fig. 3, Ep.) consists of very tall ciliated 

 cells, with numerous smaller interstitial cells at their bases. Between the tall epithelial 

 cells are scattered many large club-shaped cells (PL II, fig. 3, (il.-) full of a refractive 

 yellowish-brown secretion. 



Below the epithelium there is a thin but solid-looking basement-membrane (B.]\I.), 

 scarcely as deep as the epithelium itself. Beneath this again there is a thin layer of 

 circular muscle-fibres (C.M 2 .). A well-developed and conspicuous, deeply-staining layer 

 of large glandular cells (Gl.) succeeds this, resting immediately upon, and being partly 



