284 BULLETIN OF THE BUREAU OP FISHERIES. 



with swollen bases; at first small, they reach their maximum at about the twelfth to fourteenth pairs, 

 whence they again suffer a gradual diminution in size. The apertures of the first 17 pairs are slitlike 

 and so laterally compressed that the openings are scarcely evident; the next 10 pairs smaller and with 

 more open apertures, the aperture of the twenty-seventh where the papillae cease being wide open. The 

 following 19 pairs are very differently modified: at this point the interspace between the rows widens, 

 the suckers becoming ultramarginal and facing much more laterally; they are smaller, lower, regularly 

 and gradually diminish in size, and have wide, simple, outwardly flaring apertures. The tip of the 

 arm is occupied by a small bulbous expansion devoid of any armature save a slender pointed filiform 

 process extending distally from its pointed tip. Just proximal to the bulb and about three pairs of 

 suckers from the end, the inner surface of the arm gives rise at its middle to a very long delicate colorless 

 thread, which is so coiled upon itself that it can not be entirely straightened out without danger of 

 breaking. This thread appears to be incased in a tenuous hyaline skin, is thickest beyond the coiled 

 portion, and thence tapers to an attenuate and pointed extremity (fig. 10). 



Several of the females were examined to ascertain the possible presence of a free hectocotylus within 

 the mantle cavity, but without success. 



The dimensions of the hectocotylus above described are as follows: 



mm. 



Total length, exclusive of thread 44 



Length of papillated portion 28 



Length of terminal bulb and process 4 



Length of thread 15+ 



Maximum diameter 3 



Young: The series at hand is replete with immature specimens comprising all the later stages of 

 development, the smallest having a mantle length of about 6 mm. Great variation is evident, especially 

 in the shape and general proportions of the arms and body, but all maintain with great constancy the 

 arm formula 1, 2, 4, 3. The third arms in the smallest specimen (station 3799) are so little developed 

 as to be hardly distinguishable. All the arms are relatively much shorter than in the adult, the suckers 

 fewer and larger in comparison, the umbrella very rudimentary and about equally developed all round, 

 and the eyes rendered more conspicuous through their dark coloration. A slightly later stage (station 

 3878) shows the arms to have grown rapidly and to be already longer than the body. In males of this 

 size the hectocotylized arm is already well advanced, but in the female the extraordinary develop- 

 ment of the umbrella and attenuation of the dorsal arms does not become apparent until the animal 

 has attained a much larger size. 



Color of specimens preserved in alcohol everywhere a very pale brownish buff, the eyes with a silvery 

 metallic sheen beneath the integument. Chromatophores fairly numerous, especially just above and 

 behind the eyes, but usually more or less indistinct except in the younger specimens where they are 

 fewer in number and much more conspicuous. A single row of three to five large rectangular chromato- 

 phores commences along the base of each dorsal arm, but is soon superseded by a double series of much 

 smaller roundish ones. There is also a pair of rather large chromatophores placed transversely between 

 the eyes, a pair of similar but more widely separated ones behind them, and a single small one near the 

 center of the group. Young specimens show in addition a single line of small dark chromatophores 

 bordering the ventral mantle margin, and sometimes an aggregation of similar chromatophores forms 

 a conspicuous spot on each side of the body just behind the eyes (e. g., the individuals from station 

 3799, where both males and females appear almost different enough in this and other particulars to 

 constitute a different species; the single individual from station 3929 is the only other specimen seen 

 which shares the foregoing peculiarity). 



Type locality. — Of violaceus, the Bay of Naples, Italy; of gracilis, long. 106 W., lat. 8° N., Pacific 

 Ocean (fide Tryon). 



Distribution. — Of violaceus, Mediterranean (Delle Chiaje, Jatta, etc.); middle Atlantic; Japan 

 (Wiilker). Of gracilis, eastern mid-Pacific (Souleyet); neighborhood of the Hawaiian and Midway 

 Islands (Albatross); eastern tropical Pacific (Hoyle, as quoyanus); between Papua and Japan (Hoyle); 

 near Mauritius (Souleyet, as dubius). 



