172 Description of the Tongue and 



sion or retraction. In the Lumbricus tines, or round intes- 

 tinal worm, may be noticed fasciculi passing from the walls 

 of the abdomen to the integument, and apparently firmly 

 connected to each attachment. These transverse fasciculi 

 seem to exist nearly the whole length of the animal, and to 

 encircle the interior digestive tubes : each fibre is of toler- 

 ably visible size, and pale in colour. As these fasciculi pass 

 between the peritoneal lining of the abdominal cavity, and 

 not from the walls of the proper intestinal canal, to the in- 

 teguments, so each attachment is a fixed point, especially 

 the interior one. That they are not glands may be inferred 

 from their disconnection with the intestinal mucous mem- 

 brane, though this point can only be strictly determined by 

 the microscope. I have, however, by inspection and ana- 

 logy, been led to hold that these fasciculi are muscular and 

 perpendicular to the axis of the body of the animal, and to 

 have a similar action to the perpendicular fibres in the 

 tongue of the Cape Ant-eater. On the above supposition, that 

 their action would be to elongate the animal, without, at the 

 same time, compressing the contents of the digestive cavity, as 

 the action of circular fibres would do in producing the same 

 elongating effect. The digestive process would thus be in- 

 terrupted by such a mode of progression, and defecation 

 would otherwise only result, when the alleged circular fibres 

 were thrown into action. If any effect of the cavity of the 

 abdomen were produced by the perpendicular fibres, it 

 would be to cause a tendency to a vacuum, both by the elon- 

 gation of the animal, and also by the inner peritoneal walls 

 being made the fixed point of action of these alleged muscu- 

 lar fibres. Ingestion of food and fluids would be thus aided 

 most considerably, and independently of any provision for 

 such a purpose at the mouth. It would, however, require 

 further research to see whether analogous muscles, having 

 actions similar to those attributed to the perpendicular fibres 

 in the tongue of the Aardvark, or the body of the round in- 

 testinal worm can be found to bear out the above general 

 interpretation of their actions ; but I presume that instances 

 might be obtained to shew such a peculiar modification of 

 muscular power, and make it a more general physiological 



