156 Pelagian Mollusca collected cn a [n 0. NEW SERIES, 
believe to be true, as it is quite in accordance with its mode ofloco- 
motion^in water. The internal dorsal plate being elastic is proba- 
bly of service to the animal in making these extraordinary bounds. 
The specimen above mentioned was about 6 mches long and of a 
purple color with ten arms or tentacles surrounding the mouth, two of 
them longer than the others and all furnished with suctorial disks. 
The general form of the animal was much like that figured as Bank's 
Onychoteuthis and the resemblance also extended to the shape of 
the elastic dorsal plate but it did not possess the tentacular hooks 
characteristic of that species. 
May 5th, Lat. 30-19 S. Long. 27-4S3 W. from 5 to 8 p. ^i. 
took nothing in the net although the sate of sailing was only 
from 4 to 5 knots ; between 9 and 10 p. 3i. we got a few 
Atlanias, Fig. 7, and one or two specimens of a small com- 
pressed Hyalaa^ the form of which is well delineated in Fig. 15. 
The shell when in good condition is perfectly transparent. Habits of 
animal the same as those already described. This species we after- 
wards found had a wider range than any of the other HyaJceas 
taken by us during the voyage. In the net with these were some 
very small globose Cephalopods with prominent eyes and several 
kinds of small fish and Crustacea. One minute species in particu- 
lar of the latter class, was of a brilliant blue color. For several 
successive nights we continued to capture specimens of Hyalcea, 
Fig. 15, and occasionally Atlanta, Fig. 7. On the 9th May Lat. 
34-4 S. Long. 20-42 W. at 1 p. m. in very calm weather and the 
sky rather overcast we took in our net another species of Creseis, 
Fig. 24. It differs from the first kind in having no keel to the shell 
which is also much more elongated posteriorly and the fins of the 
animal are not fringed. Later in the day we found in the net seve- 
ral specimens of Glaucus, a Gasteeopodotjs Mollusc of singular 
form. It has on each side of an elongated body, bunches of digi- 
tated filaments, by some supposed to be branchioe, by others swim- 
ming organs. Fig. 27 was the most perfect specimen I could get 
for illustration. It was about 1 inch long. The structure of these 
animals is so delicate that when dragged astern in the net they are 
quickly destroyed by contact with other bodies. All the others when 
taken from the net had shrunk up into shapeless masses and did 
