ATLANT. DEEP-SEA EXPED. 1910. VOL. III]. 



CEPHALOPODA. 



17 



strikingly small, the funnel, which is surrounded by a are sessile. The number of suckers counted on each arm 



narrow closely fitting slit of the mantle, being long and was strangely enough constant, viz. 36. 



slender. The arms are of nearly equal length, and are joined The adjoined photograph, fig. 8, of the arms serves 



together by a web, which leaves only the distal arm-points better than words to illustrate the striking impression 



free. The following table records the size-relations:— created by the sight of the whole arrangement. We may 



Length of body from posterior end to eyes 40 mm further note that the stalked suckers are evidently out of 



Ventral mantle-length to funnel 37 „ function, being flattened and devoid of the sucking pit, 



Length of each fin 39 „ and smaller than the normal proximal suckers. 



- first right arm 108 „ If we examine the spindle-shaped sucker-stalks in the 



„ - second „ 118 „ middle part of the arms more closely, we find them to 



- third „ 100 „ consist of a gelatinous connective tissue, isolated strands 



- fourth „ 110 „ oi longitudinal muscles appearing on the surface of the 



Diameter of eye 3 „ latter, branching distally in a dichotomous manner. Out- 



The gelatinous body exhibits an 

 exceedingly faint violet colour, and 

 only the parts round the mouth, the 

 proximal section of the arms, and 

 the web exhibit the purple chocolate 

 colour peculiar to many deep-sea 

 forms. The animal being so trans- 

 parent the arm-nerves may be traced 

 throughout the entire length of the 

 arms, while in the anterior region 

 of the mantle the yellow urinary 

 sacks and the black branchial-hearts 

 are indistinctly visible through the 

 mantle. Also the ganglion stellatum 

 appears as a minute yellowish knot, 

 situated about 10 mm. behind the 

 eyes. Chromatophores are lacking, 

 with the exception of a large rhombic 

 one situated on the ventral side 

 between the two fins. 



In founding the new genus Cirro- 

 tliauma on the present specimen, I 

 rely mainly on a character which is 

 unique not only among the Cirro- 

 teuthidae but among the Octopoda. 

 If we look at the inner side of the 

 arms (fig. 8), we find them covered 

 with minute suckers poised on long 

 spindle-shaped and clumsy stalks of 

 gelatinous substance. In the middle 

 region of the arms, the length of 

 these stalks is 4 or 5 mm, but 

 towards the arm-points they gradually 

 diminish in size. The same decrease 

 in size is also noticeable in the 

 proximal direction, i. e. the stalks 

 gradually assume the form of clumsy 

 conical humps and finally disappear; 

 the 6 proximal suckers of each arm Fig. 8. Cirrothauma Murrayi. Oral aspect. The basal parts of the 8 arms visible. 



