130 VERANY AND VOGT ON THE HECTOCOTYLI 



more than 0*110 (metre) in length ; taking in this arm and its fla- 

 bellum, it measures 0*220 (metre). 



Colour, — During life this Cephalopod has a general transpa- 

 rency which allows the internal organs to be seen through the 

 body, and in the lower parts, even the chromatophora which 

 cover the membrane investing the organs of digestion and gene- 

 ration, and along the arms, the beaded nervous cord. When at 

 rest, the body glistens with iridescent hues of azure, green and 

 purple ; the pupil is of a very brilliant burnished silver, and the 

 dorsal portion of the orbits has a brilliant blue tint shot with a 

 metallic golden tinge. The chromatophora are visible only 

 with a lens, and have a purplish {mauve) tint passing into 

 violet ; when they dilate they are purple, and by the develop- 

 ment of a great number of chromatophora the dorsal surface 

 often passes into a velvety purple. When the creature is irri- 

 tated or out of the water, the chromatophora take an orange-red 

 tinge upon the lower portion ; the points are constantly larger 

 and more scattered than upon the upper. The funnel and the 

 membrane which invests the eyes are equally covered with them. 

 In spirit the chromatophora have always a wine -red colour ; in a 

 saline solution they retain their violet colour. 



The Hectocotylus is wholly white, without chromatophora: 

 the pedicle which carries it and the vesicle in its interior are 

 covered with them. 



Tremoctopus Carena, female. 



Body sac-like, oval, smooth superiorly, very slightly tubercu- 

 lated below. Branchial aperture and constrictor apparatus as 

 in the male. 



Arms conico-subulate, symmetrical; length as in the male. 

 The first pair is provided with a longitudinal membrane upon its 

 latero-superior portion, and the acetabula of the internal series 

 are united together by a longitudinal membrane, as is observed 

 also in the reticulated Tremoctopus and in the Argonaut. 



Acetabula moderate, cylindrical, excavato-pedunculated, but 

 little distant from one another ; the first pair has eighty of them, 

 the second seventy, the third sixty, the fourth eighty. 



Interbrachial membrane, mouth, funnel, and aquiferous aper- 

 tures as in the male. 



