808 REPORT OF COMMISSIONER OF. FISH AND FISHERIES. [90] 



ing it from behind and diverging in all directions to the periphery. 

 The posterior bulb remained too opaque to show its structure. Imme- 

 diately back of the head the neck was somewhat flattened for a short 

 distance, beyond which it was rather plump and cylindrical. The short, 

 flattened part of the neck was transparent, and within it could be seen 

 a band of about ten longitudinal muscles or vessels, or both. There 

 were no indications of reproductive organs. 



The specimen was next examined io oil of cloves. The character of 

 the head was now found to be quite different from what it had been 

 supposed to be when studied in the living specimen. The anterior part 

 proves to be a large globular and muscular myzorhynchus, which may 

 possibly be retractile. The central constricted part of the head is dis- 

 tinct, and surrounds the compressed base of the myzorhynchus like a 

 collar. The posterior part of the head is not strictly globular, but is 

 longer in that diameter which corresponds to the marginal diameter of 

 the body than it is in the opposite direction. It is entire in outline, 

 undivided, and at its base surrounds the constricted neck like a collar. 

 On its anterior surface it bears four supplemental disks. These are 

 oval or oblong, in shape, and are directed forwards. They appear to be 

 arranged in pairs, which are marginal with respect to the head, lateral 

 with respect to the body. They are about .Ol mm in diameter, cup shaped, 

 with depressed centers, in which there is a reticulated muscular tissue, 

 and with raised edges which are composed mainly of radiating fibers. 



The middle of the neck and anterior part of the body is traversed by 

 a number of strong muscular bands of longitudinal fibers. These 

 bands, or fascicles are distinct from certain broad sheets of longitudinal 

 muscular fibers which can also be seen in this part of the body. The 

 central band of fibers, or vessels, continues to be visible to the posterior 

 end of the body. 



The posterior bulb of the head is very muscular. The outer part of 

 it is granular with radiating and circular fibers. Of these the radiat- 

 ing fibers predominate. Beneath this outer layer towards the center 

 and the anterior part of the bulb there are numerous strong diagonal 

 fibers crossing each other so as to make a net- work with rhombic meshes. 

 The middle constricted part of the head is made up of granular tissue 

 with very numerous radiating fibers, which enter from behind and di- 

 verge to the free collar-like border. Its center is composed of longi- 

 tudinal fibers, which, entering the base of the anterior enlargement or 

 myzorhynchus from behind, make the divergent longitudinal fibers 

 which form the predominating fibrous tissue of that organ. 



The head is thus seen to be made up of three parts : First, the myzo- 

 rhynchus, which is globose in front, but contracts to a comparatively 

 narrow base. The latter is surrounded by the anterior rim of the sec- 

 ond part. This second or middle part of the head is short, separated 

 from the posterior part by a deep furrow, and surrounds the base of the 

 myzorhynchus with its anterior raised border. It may possibly be a 



