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partially divided into two layers, the fibres of the deeper layer 

 passing obliquely downwards and outwards, and decussating 

 the former. All these investing muscles which you now see 

 exposed on one side, must have the effect of moving, bending, 

 and curling this organ in every direction ; the animal can thus 

 bend it upwards over his head, or downwards between his legs, 

 or on either side along his neck. 



" On one side we have raised these longitudinal muscles, and 

 in doing so we perceive some of the principal nerves descend- 

 ing in tendinous sheaths or canals. To these nerves we shall 

 more particularly allude directly. These sheaths are con- 

 nected to the muscular fibres on either side, and resemble the 

 tendons of digastric muscles ; there are several laminae of these, 

 through and between which the principal nerves descend, and 

 are thereby protected ftom the pressure of the contracting 

 muscles, as, during the action of the latter, these canals will 

 be enlarged rather than diminished. Beneath all these long 

 muscles, but intimately united to them, we meet another por- 

 tion of muscular structure, which extends from the longitudi- 

 nal fibres, and from these tendinous canals obliquely inwards, 

 to be inserted into the parietes of the tubes. If we look at the 

 upper extremity of the proboscis, which has been cut off from 

 the skull, the course of these fleshy fibres is evident; they pre- 

 sent a radiated appearance, as they pass from the central tubes 

 outwards to be inserted, some into the longitudinal fibres, 

 others into the tendinous canals for the nerves just mentioned, 

 and others pass between the longitudinal fasciculi to the sub- 

 cutaneous aponeurosis. Some have attempted to count the 

 number of these muscles, but such an attempt is totally use- 

 less. These radiated fibres, by their contraction, can approxi- 

 mate the parietes of the tubes to the skin, and at the same 

 time compress the general structure of the trunk, and thus 

 tend to its general elongation, when the longitudinal fibres are 

 relaxed ; while by this arrangement, also, circular compres- 

 sion or constriction of the tubes is avoided, which must have 

 been the effect if the fibres pursued, a circular course. At the 



