68 



THE VOYAGE OF H.M.S. CHALLENGER. 



The Surface appears to have been quite smooth originally ; there is no sign of any 

 cirri or warts. 



The Colour is a dull yellow, apparently due to preservation in picric acid, and the 

 mantle and umbrella are thickly sprinkled with small brown chromatophores. 



Dimensions. 



Length, total, . 



End of body to mantle-margin, 



End of body to eye, 



Breadth, of body, 



Eye to edge of umbrella, 



Diameter of largest sucker, 



Length of arms, 



45 nj 

 11 



9 

 11 

 30 



0-75 

 30 



This interesting little Cephalopod came into my hands in a condition of strong con- 

 traction, due to the action of strong spirit and of picric acid, in which I infer that it had 

 been placed, partly from its strong yellow colour and partly from a statement in one of 

 V. Willemoes-Suhm's letters to the effect that this reagent was commonly used on board 

 for small Cephalopoda.^ The body of the animal was much deformed owing to this 

 contraction, and it was only after prolonged soaking in weak spirit that it was possible 

 to make out the principal points in its organisation ; indeed, it was long before I dis- 

 covered the two lateral openings into the mantle cavity, supposing in consequence that 

 this communicated with the exterior only by the siphon. There seems still to be an 

 adhesion on one side between the mantle and the body, so that access into the branchial 

 cavity on this side is impossible ; it is so clear, however, on the other that it seems only 

 reasonable to suppose that this closure is an abnormal condition. 



As regards the affinities of the genus, it seems to be most nearly allied to Cirroteuthis , 

 as shown by its arms bearing a single series of suckers and being united by a broad web. 

 They resemble each other too in the great extent to which the mantle is united with the 

 head, but in the one case the adhesion is lateral, in the other it is median. 



As conspicuous points of difference may be noted, the absence of the cartilage (so far 

 as can be ascertained by feeling through the body-wall), the absence of fins and of cirri 

 along the arms. 



In the delicacy and transparency of its tissues it also resembles Bohitwna Eledo- 

 nella and Japetella, but this may be an adaptation to pelagic life rather than a point 

 indicating morphological relationship. 



1 " Fiir Cephalopoden zarterer Art verwenden wir stets mit gutem Erfolg, ehe wir sie in Alkohol thun, eine 

 verdiinnte Losung von Chrom- oder, bei kleineren, namentlich durchsicbtigen Arten, Pikrinsaure," Challenger Briefe 

 VI., Zeitschr.f. wiss. Zool., Bd. xxvi. p. Ixxx, 1876. I may take this opportunity of recommending others to avoid the 

 use of this reagent for Cephalopoda. 



