J. MURRAY ON GASTROTRICHA. 225 



so ought to go into Ehrenberg's genus Chaetonotus. Its furca 

 was somewhat like the animal I have figured. Ehrenberg's had 

 a different furca. 



Lepidoderma sp. (PI. 10, fig. 29). 



A very small animal, with five-lobed head, apparently 

 rhomboid scales, and a short furca with diverging branches. 

 Long, tactile setae on the head. Length, 50 to 60 /x. 



The small size might lead to the supposition that the animal 

 is young. In the only instance in which I have seen a Gastrotrich 

 hatch out of the egg the young was of the full adult length of 

 the species. It had only to eat and fill out. From this I suppose 

 that Gastrotricha, like many Rotifera, do not grow appreciably 

 in length. 



I say the scales are " apparently ' rhomboid, because the 

 regular double diagonal arrangement in rows might give rise 

 to this appearance although the scales were of some other 

 form. 



Chaetonotus sp. (PI. 19, figs. SlaSlb). 



Of medium size ; trunk oval, neck well marked, head slightly 

 elongated, five-lobed, without cephalic shield. Mouth nearly 

 terminal, with tuft of hairs. 



The bristles on the head and neck are excessively short and 

 fine. At the front of the trunk they become abruptly longer 

 and thicker (though still short) and progressively longer 

 posteriorly. Near the base of the furca there are some half- 

 dozen bristles longer and thicker than any others. None of the 

 bristles are barbed. 



The scales from which the hairs spring are elongate hexagons, 

 with the angles so rounded off that they are almost oval. They 

 are arranged in regular diagonal rows, and are separated at 

 their bases by spaces about equal to the width of the scales. 



The furca is short, the branches diverging, then converging 

 (enclosing a rhomboid place), obtuse. 



No plates can be seen on the head or neck. It is the only 

 species I have seen in which the scales are visible and conspicuous 

 in a specimen in good condition. 



Habitat. Scotland. 



