156 Pelagian Hollusca collected on a [no. 2, new series, 



believe to be true, as it is quite in accordance with its mode of loco- 

 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 inches 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*40 W. from 5 to 8 p.m. 

 took nothing in the net although the rate of sailing was only 

 from 4 to 5 knots ; between 9 and 10 p. m. we got a few 

 Atlantas, Fig. 7, and one or two specimens of a small com- 

 pressed Hyalcsa, 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 Hyalceas 

 taken by us during the voyage. In the net with these were some 

 very small globose Cephalopod3 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 Hyalcect, 

 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 Gasteropodous Mollusc of singular 

 form. It has on each side of an elongated body, bunches of digi- 

 tated filaments, by some supposed to be branchice, 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 



