HOYLE: REPORTS ON THE CEPHALOPODA. 11 
be added the amount lodged in the lateral extensions of the mantle-cavity, 
which reach completely round the body, meeting behind the visceral sac. In 
those cephalopods 1n which the body is elongated antero-posteriorly there is 
à large space in the mantle-cavity, behind the gills; this may be fairly assumed 
bo serve the purpose of holding a reserve supply of water which will gradually 
pass over the gills during expiration. In the present instance, owing to the 
short, rotund character of the body, space is found for a similar reserve store of 
water at the outer side of the gills. To the outer side of each gill this cavity 
is traversed by a ligament whieh contains the pallial nerve, the ganglion stel- 
latum, and the nerves proceeding from it. The specimen being small as well 
as unique I was able to make but few observations on its internal anatomy. 
The heart is fusiform, and lies transversely : the ink-sack is small and pyri- 
form ; the renal appendages of the veins large and floccular in appearance, and 
there is the usual curved caecum at the bottom of the visceral sae. I was not 
able to ascertain the sex of the specimen, 
I have recently had an opportunity of comparing this specimen with one 
belonging to the same genus in the Hamburg Museum, which closely resembles 
Steenstrup's type. I find the two specimens agree in the following points : 
l. The form and arrangement of the suckers and the umbrella, 
The mantle-eavity extending all round the visceral sac. 
The presence of a ligament containing the stellate ganglion. 
The wide aperture of the mantle-cavity. 
E 
or 
The long siphon with intermediate ligaments. 
The principal differences are that in the present individual the arms are pro- 
portionally larger and the umbrella does not extend so near to their ends, and 
that the siphon is proportionally somewhat longer. 
Notwithstanding the difference in the radula, above alluded to, I am inclined 
to believe the specimen under discussion to be a young example of Bolitaena 
Mmierocotyla. 
Famity ARGONAUTIDA. 
Argonautidae Cantraine, '40, p. 20.) 
ARGONAUTA. 
Argonauta Linné, $58, p. 708. 
6. Argonauta hians. 
Argonauta hians Solander, ‘86, p. 44. 
Argonauta gondola Adams & Reeve, '48, p. 3, Plate 2, Figs. 2i, 2 k, 21. 
Habitat, — Station 3425, off Las Tres Marias ; April 18, 1891; lat. 21? 19^ N., 
long. 106° 24° W., 680 fathoms; green mud and sand; temperature, surface 
76°, bottom 399; one specimen, No. 8138. [H. 60.] 
