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Show 1 18 MR. W. E. HOYLE ON THE [Mar. 5, between their bases. In two cases parts of the trunk were preserved, but in no instance was there anything like a complete specimen. In consequence, I have been unable to give any account of several organs, and m y descriptions of others are lamentably incomplete ; but it seemed better on the whole, in view of the rarity of this species, of its unique external characters, and of our almost entire ignorance as to its anatomy, to utilize the material at hand and endeavour to throw light upon the somewhat obscure relationships of this remarkable form. It is perhaps worth while to mention the order in which the digestive process seems to attack the various parts of the body. The cuticle very soon disappears, then the fin becomes detached, and the posterior end of the pen is dissolved, being probably of a softer consistency than the shaft. Then most of the hooks and suckers become detached, and the tentacular clubs lose the greater part of their armature. The digestive organs and genital glands disappear, and the gills become disorganized, the circulatory organs persisting longer. The head with its attached arms then separates from the body. The nervous tissues are very persistent. The last portions of the body to remain are the mandibles and the lenses of the eyes, which often occur in the stomachs of Cetacea in considerable numbers. Regarding the external description and history of this Cephalopod I may refer to m y ' Challenger' Reportl and to the authorities therein quoted2. The only published information known to me regarding its internal anatomy is about half a page in Verrill's Monograph of the Cephalopods of N.E. America 3. Its peculiarities are such that I have ventured upon the step of creating a new subfamily for its reception, and it was therefore a matter of special interest to ascertain that this procedure was justified by the internal structure. For the convenience of the reader I may be allowed to recapitulate here the chief peculiarities of the species, as it will be necessary to refer to them in the subsequent discussion. 1. The Arms have each four series of suckers or hooks, whilst all the other (Egopsids have only two. 2. The Ventral Arms possess only suckers in all the four series, whilst the other arms have two series of suckers along the margins and two series of hooks up the centre. 3. The Tentacles are furnished even from a point low down upon the stem with regularly disposed longitudinal series of small suckers and corresponding fixing-cushions. 4. The Connective Apparatus is continued up one side of the club, where it forms a group of five or six large suckers and fixing-cushions, whilst the middle of the club itself is occupied by a very short series of two large and three very small hooks, and the tip of the club is covered with small suckers. 1 Eeport on the Cephalopoda. ' Challenger,' Reports, Zool. vol. xvi. part xlvi. p. 174 (1886). 2 Especially Steenstrup, Oversigt K. D. Vid. Selsk. Forhandl. 1881. 3 Trans. Connect. Acad. v. p. 393 (1881); also Rep. U. S. Fish Com. for 1879, Washington, p. 418 (1882). |