OOLLECTION OF NEMERTEANS FROM SINGAPORE. 138 



it as shallow depressions. A caudal appendage is present. The 

 colour is olive-green above, becoming slightly paler below. A 

 broad white transverse band occurs round the snout near the 

 tip. The tip of the snout is nearly black (fig, 14). 



The epithelium contains numerous greenish unicellular 

 glands (fig. 2b, ep.). The cutis contains the usual circular 

 and longitudinal layers of muscle fibrillfe. Cutis glands are 

 absent except for two longitudinal streaks anteriorly at the 

 level of the head slits (fig\ 25, a. and hcgl.). These glands 

 do not stain appreciably with hfemalum, but take a vivid 

 stain with eosin. The connective-tissue layer is well marked, 

 and contains a few muscle-fibrils except beneath the cutis 

 glands. Behind the oesophageal region there are no gland 

 cells in the cutis. 



The muscle layers are of the usual order, the outer 

 longitudinal layer being considerably thicker than the other 

 two together. A horizontal layer occurs over the month. 

 There is no diagonal layer. 



The vascular system is of the usual type, and there is a 

 well-marked head loop. 



The alimentary canal presents no special features. 

 The dorso-ventral musculature is very weak. The ventral 

 gutter is very small. 



The proboscis is missing in both cases. 



The generative organs contain immature ova. 



The excretory system commences before the termina- 

 tion of the cerebral organ, and lies, for the whole of its short 

 extent, entirely dorsal to the level of the side stems. The 

 excretory duct is given off about the middle (fig. 40). 



The nervous system shows no special features except 

 that the brain lobes are rather high and short. The median 

 nerve is indistinguishable. 



The cerebral organ is lai'ge compared with the size of 

 the brain, its extent from before backwards being rather 

 greater than that of the brain. The dorsal lobe of the 

 dorsal ganglion ends just as the cerebral organ commences. 

 Dorsal and ventral glands are both well developed (fig. 29, 



