EXPLANATION OF THE PLATES. 
All the figures were drawn from nature by Mr. J. H. Emerton, except when other- 
wise stated.* 
Plate XXVI. 
Figure 1 .—Architeuthis Harveyi V. (Xo. 24). Young. Pharynx and beak, with 
odontophore; o, oesophagus, natural size. 
Figure 2. — The same. Distal part of tentacular arm. with club, natural size. 
Figure 3.— The same. Segment from distal portion of left arm of the third pair of ses- 
sile arms, front view; 3a, the same, side view, natural size. 
Figure 4.— The same. Basal portion of right arm, of second pair. Front view, 
natural size. 
Figure 5 .—Architeuthis Harveyi V. (Xo. 2). One of the marginal suckers of the 
club, side view ; 5a, the same, front view, enlarged 2 diameters. 
Plate XXVII. 
Figure 1. — Desmoteuthis hyperborea V. Ventral view of a female, 4 natural size. 
Figure 2. — The same specimen. Dorsal view of head and arms. Part of the arms 
are imperfect. 
Figure 3. — Histioteuthis Coll ins ii V. Original type. One of the tentacular arms. 
Front view. 4 natural size. 
Figure 4. — Beak of the same specimen ; a, upper, b, lower mandible, natural size. 
Figure 5 —Suckers of the same specimen: a, side, and a', front view of one of the 
larger suckers of lateral arm ; b. side, and b' front view of a distal sucker, 
enlarged 2£ diameters. 
Figure 6. — Sthenoteuthis megaptera V. Side view of jaws and odontophore. natural 
size. 
Figure 7 and la. — Sthenoteuthis pteropms V. Upper and lower mandibles, natural 
size. 
Figure 8. — Rossia Hyatti V. Side view of young male, natural size. 
Figure 9. — The same. Egg containing an embryo ; enlarged 6 diameters. The 
shaded portion represents the yolk still remaining unabsorbed. 
Figure 10. — Onychoteuthis Banksii. One of the large hooks from the middle of the 
club; a, side view; a', front view ; enlarged 4 diameters. 
Figure 11. — The same. Corresponding views of one of the smaller hooks of the club. 
Figure 12. — The same. Homy ring from one of the small suckers on the proximal 
cluster of connective suckers and tubercles of the club ; a, side view ; a', front 
view, enlarged 4 diameters. 
* Most of these figures were drawn in India ink, by Mr. Emerton, for the U. S. 
Fish Commission, to be engraved in relief, to illustrate a report on the Cephalopoda by 
the writer, which has been printing nearly simultaneously with this article in one of 
the volumes of the report of Professor S. F. Baird, the Commissioner. To Professor 
Baird I am greatly indebted for the privilege of first using a large part of the draw- 
ings here, which has enabled me to illustrate this article more fully than would, 
otherwise, have been possible. 
