22 DR. R. E. GRANT ON THE GENUS LOLIGOPSIS, 
velopment of the tentacula, which are the most mutable of the parts around the mouth, 
assuming various forms, and being sometimes entirely wanting. They are present in 
Loligo, absent in Octopus; and in the animal which forms the subject of this commu- 
nication, they are perceptible only in a rudimentary state. The Cephalopods present 
differences of structure so remarkable as to render it impossible, in the present state 
of our acquaintance with them, to determine what characters even of an external 
nature are incompatible with each other, or necessarily concomitant. 
The Cephalopod represented in the accompanying drawings (Plate II. figg. 2. & seq.) 
was taken in the Indian Ocean by my late intelligent pupil Mr. Cotton, Surgeon in the 
Honourable East India Company’s service, and was sent to me along with many other 
interesting marine animals collected by him during his second voyage to India. It 
has the lengthened tapering form of body, the eight sessile arms, and the circular 
caudal appendix of the other two known species of Loligopsis ; but it differs from them 
in the comparative length of the different arms,—a character by which they also differ 
from each other. The Loligopsis Peronii, according to Lamarck, has the eight arms of 
equal length ; the Lol. cyclura, according to M. Le Sueur, has the upper and the inferior 
pair of arms, nearly of equal length ; and in the Lol. guttata the upper pair of arms are 
at least a third shorter and smaller than any of the other pairs. The whole length of 
the present species, from the point of the longest arms to the end of the tail, is four inches 
and three quarters ; the specimen of M. Le Sueur measured five inches and ahalf; and 
that of Lamarck was like a small Sepiola, that is, about two inches long: so that this 
singular type is probably confined to small Cephalopods, and has thus escaped more 
general observation. Independently, however, of its external peculiarities, it presents 
modifications of internal structure hitherto met with in no other Naked Cephalopods, 
and which serve to connect the latter forms with the Testaceous. 
Externally this animal! has much resemblance to a young individual of the common 
Loligo sagittata deprived of its long tentacula. It has the same lengthened tapering 
form of the body, short cephalic arms, dark brown spotted surface, and rounded ter- 
minal fin. Every part of the surface, from the point of the arms to the extremity of 
the tail, is closely covered with dark brown spots, chiefly of two sizes; the larger are 
minute angular patches of irregular form, and the smaller are very minute dark points, 
filling up the interstices between the polygonal patches. These spots extend into the 
interior of the mantle, and cover closely the surface of the four separate lobes of the 
liver. There are several large, round, and very obvious patches of the same deep brown 
colour on the caudal half of the trunk, which have a somewhat symmetrical arrange- 
ment; eleven of these are seen on the dorsal surface, and nine on the ventral. It is 
not probable that these large circular spots will be found identical in number and ar- 
rangement in other species, although from their size and symmetrical order they may 
be constant in this ; I have therefore taken the trivial name of the present species from 
1 Plate II. figg. 2. & 3. 
